Boolean operators -- AND, OR and NOT -- are used to establish relationships between key words and keyword phrases. These operators can be used to expand or narrow a search and must be typed in ALL CAPS.
The AND operator locates articles that contain all of the key words or phrases.
Example: A query such as children AND computers returns articles that contain both key words.
The OR operator locates articles that contain at least one of the key words or phrases.
Example: A query such as hurricane OR tornado returns articles that contain one or both key words.
The NOT operator eliminates articles that contain certain key words or phrases.
Examples: A query such as basketball NOT college returns articles that contain the word basketball but not the word college.
California AND earthquake NOT "San Francisco" returns articles that contain the words California and earthquake but not the phrase San Francisco. This is an example of how to locate references to the various earthquakes in California, excluding those in San Francisco.
UseAND and OR together to expand your search. AND has a higher precedence than OR, so you must enclose the OR words in parentheses.
Example: health AND (kids OR children) returns articles that contain the words health and kids, or health and children.
Use NOT and OR together to limit your search. NOT has a higher precedence than OR so a search using NOT and OR, produces results as described below.
Example: (dog NOT cat) OR puppy returns articles that contain the word dog but not the word cat, or that contain the word puppy.
Note: The AND operator is implied between each key word or phrase in a query that does not contain Boolean operators. See Natural Language Search.
Truncation is a shortcut used to include alternate word endings in your query. This is a quick and easy way to include plurals, tense variations and alternate spellings.
To use Truncation, type an asterisk (*) after the root of your key word. For example, the query farm* returns articles that contain the words farm, farmed, farmer, farmers, farming, farmland, farmhouse, farms, etc.
Phrase Search allows searching of article text for keyword phrases. The phrase must be enclosed in quotation marks to ensure that the entire phrase is searched for in its entirety, rather than the individual words in the phrase.
Entering the query "San Francisco" only returns articles that contain the phrase San Francisco, rather than articles that may include either word separately such as San Antonio, San Andreas Fault, Anthony Francisco Giacossa, etc.