You can combine your search words and phrases using the Boolean Operators: AND, OR, and NOT.

These words can be used to narrow or expand your search.

AND

All search terms must be found in each result e.g. smoking AND cessation finds results with both search terms.

This reduces the number of results.

Note: Google Scholar, PubMed and Search Everything on the library homepage will automatically join your search terms with "AND".

Narrows your search.

Fewer results.

OR

The results of your search must contain at least one of the search terms e.g. smoking OR cigarettes OR tobacco will find results containing any of these words.

Use OR between your synonyms to ensure at least one of your search terms is present.

This increases the number of results.

Note: If using Google, Google Scholar or PubMed - "OR" must be in capital letters.

Broadens your search.

OR = More

NOT

The search term following NOT will be excluded from your search. Results will not contain that search term.

e.g "nicotine replacement" NOT "nicotine gum" will exclude results which contain the phrase nicotine gum.

This decreases the number of results.

Narrows your search.

Fewer results.

Boolean operators

Watch the video (2:43) below to find out about Boolean operators:

Basic Boolean Video transcript (pdf - 40KB).