Depending on the database, it may offer a variety of ways to limit your results:
For articles that are not available in full text, use the InterLibrary Loan service.
Most databases use a controlled vocabulary to organize information and make browsing more efficient and specific to chosen terms. When building your search string, consider keywords, synonyms, or related terms.
Combine or group terms or concepts using the Boolean operator "AND" to refine your search string: native american history AND 20th century, or native american history AND Oklahoma, or try the search string: creek indians AND oklahoma . Check to see if the database offers a Thesaurus or a Subject Terms tab or link. For instance, the database Academic Search Premier offers a "subject terms" tab, and the Military & Government Collection database features a "subjects" tab, while ProQuest offers a "thesaurus" link. Enter terms in the Browsing box to see how the database recognizes them.