Specify one or more words to use as a search query for finding Best Match information. By default, keyword queries search item titles only. If you repeat this field in the request, the BestMatchItemDetails Service only recognizes the last keywords field.
The words "and" and "or" are treated like any other words; use "and", "or", or "the" only if you are searching for listings that contain these words.
You can incorporate wildcards into a multi-word search, such as "ap*%20ip*". In this case, the response can contain results for "apple ipod", among other matches.
If you are using a URL request and your keyword query consists of multiple words, use "%20" separate the words. For example, use Harry%20Potter to search for items containing those words, in any order.