Every profession has a journal devoted to it and if you're interested in, say, librarians, then you'll want to read American Libraries. Mechanical engineers read Mechanical Engineering Magazine. If you can't find the trade journal that you're looking for, ask a librarian.
(These techniques will work in both the library catalog and WorldCat.)
To be certain that you're looking at all of the books on a particular topic, it can be useful to search the official library subject for that topic. Sometimes the library subjects are not intuitive, sometimes they are. There may be more than one subject term that you'll need to look at for your topic -- both migration and immigration, perhaps. You can use either the basic or the advanced search options to search for subjects, use the pull-down menu to select "subject."
Depending on what you're studying, you may need to find articles on the topic. There's a source for articles on any subject! Check out the research guides that librarians have created, for starters. For example, here are two good anthropology sources from the anthropology research guide.