Use keywords to make a concise search query and avoid full sentences or too many words - this will yield better results :).
For example, Mexican Americans and activism.
Combine the name of the group you are studying with the aspect you want to find out about. For example,
Chican* AND (combine with one of the following):
Note: using the asterisk (shift 8), like in the example above, is called truncation. For example, Chican* will search for Chicana, Chicanas, Chicano, Chicanos, Chicanx, Chicanismo, Chicanidad, etc.
Newspapers, magazines, and scholarly journals published by and about various racial and ethnic groups in the United States.
Background information from general and subject encyclopedias.
Scholarly journals, professional journals, reports and magazines in the social sciences, the humanities, and general sciences.