For information on the topic or theme of a documentary, the Opposing Viewpoints database is an excellent place to begin your research. Good critical thinking demands that you consider various point of view on a topic. This database collects articles that represent various sides of issues.
A few examples of topics covered in this database:
Or try out the Topic Finder
A good way to find information about a filmmaker or a film is to read reviews. You can find reviews online, but better sources may be found through these databases.
Search for the title of the film or the name of the filmmaker and add the work review.