Combine search terms for greater precision and relevancy of results. This technique works best with databases and search engines, because the terms used will can be quite precise. Library catalog records may use broader, more general terms, but combining search terms is always worth a try.
AND will limit results. The search below will eliminate anything that doesn't include all three search terms (phrases):
food industry AND sponsorship AND education
OR will expand results. The search below will retrieve all records including either one phrase or the other. Note: the search would be stronger if quotations were used to bind the terms together.
food industry OR food corporations
OR will retrieve all the results symbolized in the diagram below.
NOT eliminates a search term or phrase from the results. It's helpful when your searches retrieve materials irrelevant to your topic.
"public schools" NOT "public television"
With this example, only the records symbolized by the blue portion are retrieved.
Field searching means to restrict a search to a specific field in a record. This is a common technique and can be applied in the library catalog, databases, and in advanced web searches.
Library catalog search box and options for field searching. Use "anywhere" if you don't know precise title, author, or subject words.
Field searching in EBSCO's SocINDEX with Full Text. Note the added field options.
Google advanced field search instructions for text and other options.
A. Combining terms or phrases directs the search engine to either expand or limit its results.
1. AND will limit results: food stamps AND restrictions will retrieve records that include BOTH those terms
NOTE: This search can be made stronger by changing the terms to "food stamps" AND restriction*
- Quotations will bind a phrase together. Results will include the phrase "food stamps"
- An asterisk serves as a truncation symbol (see right box),
2. OR will expand results: "food industry" OR "food corporation*" OR agribusiness OR "food compan*" will retrieve records that include ANY of these terms
3. NOT will limit results and is used to filter out unwanted topics: "school lunch program" NOT charter schools
B. Another way to promote precision in searching is to use subject headings rather than keywords. However, subject headings can differ by database, making a subject heading search less effective.
C. Nesting: Nesting with parentheses provides the search engine with important information about the order of a search.
Truncation in searching means that the search term (or keyword) is shortened to the stem of the word. Word endings (suffixes) are removed.
sponsor* will search for the keywords