Searching with Boolean Operators: AND, OR, NOT

You can use Boolean operators to join search terms to improve the number and quality of search results. Three Boolean operators are available: AND, OR and NOT. Note that the operators must be entered in uppercase letters in order to be recognized as operators.

operator_or

operator_and

operator_not

The OR operator increases the number of search results

Parsons OR System

finds any references that contain the search term Parsons, any references that contain the search term System, as well as any references that contain both search terms Parsons and System.

The AND operator reduces the number of search results

Parsons AND System

finds only references that contain both of the search  terms Parsons and System.

The NOT operator reduces the number of search results

Parsons NOT System

finds references that contain the search term Parsons but do not contain the search term System.

When using multiple search terms with multiple operators, use parentheses to make sure your search intent is clear:

Parsons OR Luhmann AND System finds references that contain the search term Parsons (but not necessarily the search term System) as well as references that contain both search terms Luhmann and System.

(Parsons OR Luhmann) AND System finds references that contain the search term System combined with either the search terms Parsons, Luhmann, or both.

To search for a specific phrase, place it in quotation marks: "social system"

Hint: You can use field names, search terms, Boolean operators, and parentheses in a quick search, too.