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Boolean Searching

Broaden or narrow your search by combing words or phrases using the Boolean operators AND, OR, and NOT.

The results of performing Boolean searches are sometimes illustrated by the diagrams below (called Venn diagrams.) The diagrams show graphically how using the AND operator narrows a search, using OR broadens a search, and using NOT excludes material from a search.

Many databases and search engines have an Advanced Search interface that allows for Boolean searching; you can also try just using a Boolean operator in the main search box.

Operator	Example search	The search will find...	Venn diagram results shown in pink
AND	television and violence	items containing "television" and "violence." AND narrows a search, resulting in fewer hits.
OR	television or mass media	items containing either "television" or "mass media " or both. OR broadens a search, resulting in more hits.
NOT*	stress not anxiety	items containing "Stress" but not "Anxiety." Caution! It's easy to exclude relevant items.

Parentheses (Nesting)

Use parentheses to clarify relationships between search terms.

Example: (television or mass media) and women

This search looks for both "television and women" and "mass media and women."

Truncation or Wildcards

A symbol at the end of a word stem provides for all variants on the word stem. The most commonly used symbol is the asterisk (*).

Example: educat* will retrieve educate, educating, education, educational, educator, educators, etc.

Be careful not to truncate too far, or you will retrieve unrelated words!

A symbol within a word provides for all possible variants inside a word or word stem. A commonly used symbol for internal truncation is !or ? .

Example: wom!n will retrieve woman and women.

You may combine truncation symbols in one search.

Look at the help pages for the database you are using to determine the truncation symbols. Most systems provide truncation but some provide only simple plurals.