One of the main benefits to doing research with library databases over Google is that a real, live human being read the documents in these databases and assigned a set vocabulary--known variously as tags, subject headings, or descriptors--to describe the texts' intellectual content. In GEORGE and most other US academic library catalogs, the tags are called Library of Congress Subject Headings (LCSH). LCSHs are a specialized vocabulary created by the Library of Congress to describe titles uniformly across thousands of libraries.
If you search by subject heading, you know you will retrieve documents that really address that term/topic rather than just contain the term. By contrast, searching by keyword retrieves every document containing your term, even if the entire document is not focused on that keyword.
Sample Subject Headings (Tags):
Searching by Keyword allows you to use the “natural language” you’d normally use to describe a topic (or with terms specific to the late 18th century through the pos-Reconstruction era if you're searching in a primary source database), combined with the operators AND, OR, and NOT. Scan the results to identify the official subject headings (tags). Be flexible by trying several keywords as shown below on the "10 Steps to Successful Searching" handout. Example:
(international OR foreign) AND (United kingdom or UK or England) AND (trade* or business or investment)