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Help with Library Research

Boolean Operators: AND, OR, NOT

Phrase Searching

To search for a phrase (words in the exact order), put quotation marks around the phrase. It's possible to combine words and phrases in a Novanet, a database search, or even a Google search. If you do not use quotes, you will find items that contain the individual words, but not necessarily in the order you specified.


electric car finds the words electric and car anywhere in the items

"electric car" (with quotation marks) finds only items containing the exact phrase in that order.

Video: Subject Headings vs. Keywords

Subject Headings Advantages & Challanges

Subject headings are an established set of words or phrases that are used to describe or classify articles in a database. 

Unlike keywords which are a match made by the computer between what you entered and what exists in the item records (authors, titles, abstracts, etc.), the subject headings are applied by staff employed by the database companies. The subject headings represent the main essence of the articles. 

  1. Helps with synonyms and related words.
    With subject headings, you do not need to know all the possible words that could potentially be used in a research article. You just need to know what the subject heading is. This can help to make up for unfamiliarity with a topic or area of study. One of the challenges of searching using keywords is that some terms can have many related words. For example, the term social media is also related to social networks as well as online networks. In addition, articles featuring different types of social media platforms, like Facebook, Reddit, InstagramX (formerly Twitter), etc. will also be relevant, but may not use the phrase "social media". We could use the Boolean term OR to connect all the terms, but there is always a chance that we have not thought of all the possible terms.

  2. Helps achieve a more focused search.
    Subject Headings are arranged from broader terms to more specific terms.


Broadest term:
mmunication to represent all types of communication.

Narrower term: 
Social media is a narrower term related to communication within online communities. This is narrower than communication but still encompasses many types of online networks and communication.

Narrowest term:
Finally, you can have narrower subject headings such as blogs, which concern themselves with one type of social media.

This is an advantage because depending on your topic and what items are available, you may need to make your search narrower or broader. The Subject Headings structure provides some guidance on the terms to use to broaden or narrow your search. It can also provide related terms.

  1. Subject Terms may be different from commonly used terms for a topic.


GMO or genetically modified seeds (the term we may want to use)
Transgenic seeds (subject term in use)

Gender role (the term we may want to use)
Sex role  (actual subject term in use) 

  1. When a database does not provide a thesaurus or list of subject terms, the controlled vocabulary may not be obvious.
  2. Human error: Subjects must be applied consistently for the catalogue or database to remain useful.
    There is always a tension between currency and consistency.

Where to find Subject Headings in Article Databases.

Where to find Subject Headings in Article Databases.

  1. Subject headings are a field included with every database record. The will appear under the title on the search results page and are also listed on the item details page.
  2. If you know the subject heading, you can search for the term with the Subject Terms field in the search box.
  3. Many databases also include a subject headings look up tool. It is usually located at the top of the page. This is sometimes called Subject Terms or Thesaurus or Subjects. 
  4. Subject headings also appear in the search result filters (located either on the right or left column of the page depending on the database). Please note that filters always narrow your results. These will result in fewer more focused results.

Image shows location of subject headings information on the database results page

Truncation & Wildcards

Searching Effectively Using Truncation

When you are doing searches in databases, you can make your searches more effective by using something called TRUNCATION. [Use the next button at the top of the screen to navigate through the tutorial]

Imagine you are looking for an article about the dangers of driving while using a cell phone. You type “cell phones and driving” into your favorite library databases. Alas, you’ll miss an article like: “Cellular phones: is it safe to drive and talk?”

For example you searched for “cell phones and driving” and results are items like, “Driving with cell phones” and “Cell phones and safe driving”]

Luckily, there’s a solution: Truncation

Truncation uses symbols (or wildcards) to replace letters in words. You can use them to get more results than you would with one word. 


Different databases, catalogs, and search engines use different symbols. Some of the most common are

* (asterisk)

? (question mark)

# (pound sign)

For example cell*, will retrieve cell, cells, cellist, cellophane


What does that mean? Instead of searching for “cellphones and driving”, you could look for “cell* phone* and driv*”.

cell* finds cell, cells, and cellular

phone* finds phone and phones

driv* finds drive, drives, and driving

“Cellular phones: is it safe to talk and drive?”


Truncation works in many: 

  • search engines

  • databases

  • library catalogues


Why use truncation? 

  • Find plurals. 
    • Search teacher* and training and you’ll find info about “training teachers” and teacher training”

  • Not all search engines take into account the difference between Canadian and U.S. spelling.
    • Looking for contemporary theatre? Search for theat* and you’ll find theater, too. 
  • Find related concepts that are spelled similarly. 
    • Psych*ic would find psychic, psychotic, psychopathic, or psychopathologic. Add another asterisk at the end and you’d find the plurals, too. 

  • Maybe you can’t remember the correct spelling of a term or place. 
    • Working on a country study and can’t remember how to spell Azerbaijan? Search for Azer*


Truncation Pitfalls

  • You may get more than you want. Truncating some words, especially short ones, can give you a lot of irrelevant results. 
    • Looking for a good Web site on cats? Using cat* will find cat and cats, but it will also find catapult, caterer, cathedral, catamarans, and logs more. Try (cat OR cats) instead.

  • Really short words. Some search tools won’t let you truncate to less than three or four letters. 
    • Using al* to find allelomorphism probably won’t work. Better learn to spell it.

  • Symbols aren’t standardized
    • Different tools use different wildcard symbols. 
    • One database might use # instead of *. To find libraries, library or librarians…
      • Database 1: search librar*

      • Database 2: search librar#

    • Some search tools have a character which replaces only a single character. For example:
      • dog? might find dog or dogs.

      • dog* might find dog, dogs, dogged, dogma and dogmatic.