Decide on a particular angle before starting the research process.
What really grabbed your attention from the book? Maybe a certain character intrigued you. Instead of searching the character's name, search the ideals or motivations of the character instead.
If you are interested in researching Simon's kindness:
Here is a sample concept map for Lord of the Flies.
You may discover that your initial thesis is not quite right or needs to change to something that can be argued with the evidence you have found.