Chapter $2$ discusses three major information finding tools; web search engines, library discovery tools, and article indexes.

Why would you use multiple finding tools when looking for information?

Each can help you find different sets of sources for a more complete understanding of the topic

To find all relevant news sources and websites on your research topic

To make sure you find every possible source that addresses your topic at all

To avoid a temptation of using only one finding tool during your information gathering process

No need to use multiple finding tools, Google finds everything you need on your research topic