ItemSearch's Power parameter, which can only be used when the search index equals Books, enables you to use simple or complex queries to perform book searches. A simple power search would be to return all books written by a specified author. While this query is valuable, it does not offer anything more than a similar search using the Author parameter in an ItemSearch request.

The true value of power searches comes in the ability to specify multiple criteria to search for books. For example, you could create a query that returned all books by a specific author, published during a specified year, in a specified language, and printed in a specified format.