By default, the results are listed in order of relevance, similar to a search engine like Google. The relevance is determined using a number of factors, including how often and where the search terms appear in the item description, and whether the search terms are part of the title, subject, author, or series. The results which best match your search are returned first rather than results appearing in alphabetical or chronological order.
In the Advanced Search screen, you may select to order the search results by relevance, title, author, or publication date before you start the search. You can also re-order your search results using the Sort Results dropdown list on the search result screen.