Keywords are important. Using the right words makes your search easier and gives you the results you need for your papers. But finding the rights words can be hard. There are lots of ways to keep track of keywords - just be sure you keep track of them so you don't end up using the same words over and over to the same search results over and over.
"Keywords are the significant words or concepts that express an idea or topic. They are an example of "natural language" access to information, in which you use words in natural order to describe a topic. In contrast, Library of Congress subject headings are examples of a "controlled vocabulary" access to information. A keyword search finds the word or phrase you choose in any field of the catalog record. Keywords are also used for searches in computer-based periodical indexes and Internet search engines.(Elmer E. Rasmussen Library, Nov 8, 2014)."
Here's an example of a mindmap. The student used colors to organize her ideas: red is the idea she started with, green are broader concepts, black are subtopics. She put a red star on the topic she decided to focus on.
Attribution: Clark College Brainstorming LibGuide located at http://libraryguides.library.clark.edu/brainstorming
The full worksheet is located at Generating Keywords Worksheet. It is from the ACRL Information Literacy Sandbox CC Attribution License CC-BY
Although this source is primarily for business, it has a robust keyword finder! Try it out - Wordtracker
This is another business based keyword searcher but with some cool graphics. Try searching philosophy...Answer the Public