To identify germane subject headings, first do a logical keyword search in the catalog, then find one or two relevant titles and look at the full records to determine the subject headings assigned to them. Try searching those headings to expand your search. If there is no one subject heading that incorporates all the disparate elements of your search, you will at least have determined the subject terminolgy. Sometimes, however, keywords or keyword phrases may still be the most productive.
Keyord Search: 9/11 terorism
Subject Heading: September 11 Terrorist Attacks, 2001
Keyword Search: rendition
Subject Heading: Extraordinary rendition -- United States
Keyword Phrase: "transnational violence"
Potentially Useful Library of Congress Subject Headings:
This Library of Congress Classification Outline holds true for any library in the world using the LC system. Political Science will be classed in the Js, Military Science in the Us, & Naval Science in the Vs.