Amazon KINDLE Manual page 50

The features on the Search Results page are explained below.
Instances — shows the title of the items that contain your search term and indicates how
many times the term occurs. The list is ordered by the number of occurrences of the
search term in each item, however, if the term is found in the book you are currently
reading, it will be listed first regardless of the number of occurrences.
More results available — shows the entire list of items that contain your search term.
This feature is only selectable if there are more results than fit on the current page.
Un-indexed items — displays the number of items that are not yet indexed for search.
When new content arrives on Kindle, it takes a few minutes (depending on the size of the
item) to index the text inside the reading material so it can be searched. This happens
automatically in the background or you can select and view an un-indexed item to update
now to make it searchable sooner.
Dictionary — displays the number of definitions from the selected default dictionary.
Search Wikipedia for search term — select this to search for a term for free on
Wikipedia, the online encyclopedia.
Search Web for search term — select this to search for a term on the Web.