Google is good at ignoring words that don't relate to your topic (like "the," "a," "why," etc.). Databases usually take your search literally, so only search for the main ideas for your topic.
Don't assume a database ranks relevant results like Google. In databases, refine your searches to have a manageable number of results.
Choose words that would appear in your desired result. For academic research, use terminology that would be used by scholars in that discipline.
To discover search terms, try a glossary. For example, a Google search for "anthropology glossary" gives several good results. You could also look for terms in a textbook or other background information, in a disciplinary database's subjects list, or by talking to your professor.
Keywords are any words that appear in the text.
Subjects are terms assigned to a source that accurately match the overall content.
To discover subject terms, browse for subjects in the database that match your topic. Look for a button or link that says Subjects, Index, or Thesaurus (check the Help screens). Alternatively, perform a keyword search, and in your results, look at the Subject or Descriptor field to note the terms used.
Use quotation marks around a phrase for results that only have those words in that order. Alternatively, look for a drop down menu that designates the search box to be "exact."
These Boolean operators connect your search words together to either narrow or expand your list of results.
Truncation broadens your search results to include various word endings and spellings.
Wildcards substitute a symbol for one letter of a word.
Too many results
Too few results
Some results may only be citations, but you can easily get full text.