General database via EBSCO that covers a wide range of research resources, including core subjects such as applied science, art, education, humanities, law, social science, business, and technology. A good place to start research.
Public Affairs Information Service: Political Science, Criminal Justice, and Public Administration and includes journal articles, books, government documents, statistical directories, grey literature, and publications of international agencies.
A digital interdisciplinary archive of over 1,000 leading academic journals in the humanities, social sciences, and sciences. JSTOR also includes other valuable materials for academic work, such as select monographs, photographs, manuscripts, speeches, maps, and pamphlets. All collections are full-text searchable, offer search-term highlighting, include high-quality images, and are interlinked by millions of citations and references.
Need to find full text newspaper, magazine, reports, and journal articles relating to the impact of gender across a broad spectrum of subject areas including business, education, arts, literature, health sciences, political science, sociology and much more? Try GenderWatch!

Standard three-box search engine:
This example comes from Sociological Abstracts. Most article databases will have similar three-box search. This example illustrates a search on "college student's attitudes toward alcoholism" In this case, the database only display 2 boxes but additional lines can easily be added by clicking on... add a row.
And used to limit a search
AND produces results that include both terms
Example: treatment and recovery
Or used to broaden a search
OR Includes in the search each of the terms
Example: alcoholism or alcoholics
Not used to exclude terms
NOT will produce results that exclude a term
Example: NOT college students
produces results that do not include college students