What questions do you still have?

Although we have studied boolean operators I still don't understand where to use them. WHen doing research the default boolean operator puts in either "and" or "or" and both brings up whatever I am searching. But then we were also told that adding "and not" helps restrict the search from looking for certain words yet not all search engines recognize these boolean operators unless you do an advanced search which I do not really know where to find. Some search engines supposedly allow the plus or minus sign though so I guess if I get more familiar with that then I can restrict and narrow down my results more efficiently.