Most efficient way to gather information for 4,000 word research paper?

I have to write a 4,000 word research paper and I want to know what is the best way to get the information I need out of my book sources, because they're all pretty long. But keep in mind that I have to demonstrate a full knowledge of my topic.

Most efficient way to gather information for 4,000 word research paper?
It kind of depends on your topic which you didn't tell us. You can probably read the table of contents in the books and see what chapters might contain the information you need. You could do a google search but be careful, because most of the information on the internet is garbage. You might want to start with the Encyclopedia Britannica to give you a good idea of what you are looking for. However, if you are 9th grade or higher, I wouldn't list that as a source unless you take a quote from it.