Handbooks, and specifically research handbooks, can provide very valuable overviews of past theories and current thinking on aspects of a particular subject or discipline. They are generally edited volumes, with chapters written by experts in the field, and these usually include extensive bibliographies of key writings on the topic treated in the chapter.
To search for Handbooks in Educat+ change the search field to subject and try this formula: "[your subject] -- Handbooks, manuals, etc." Take a look at this searching by subject guide to learn more about how to construct searches like this.
Columbia University Libraries also has access to handbooks of research. In CLIO Databases search, adjust the field "Browse by Research Type" to "Handbooks" and search for the topic you are looking for. You can also adjust the "Browse by Discipline" field to narrow your results.