Identify the key words that describe your topic and use them to search the library catalog and databases. Make a list of synonyms and search with those, too. Enclose words in "quotation marks" when you want multiple words to express one idea or concept.
"weimar classicism" and schiller
Use the words AND, OR, and NOT--called boolean operators--between your keywords to broaden or narrow your search.
schiller and (plays or poems)
If you shorten, or truncate, a word and then use an asterisk to "stand-in" for its different endings, your search results will include all forms of the word.
A key word search for drama* will look for drama, dramatist, dramatists, dramatic--