All searches in JReviews use LIKE to retrieve results. To use an exact word match, it would be necessary to use REGEXP because there aren't any fulltext indexes.
The following filter allows adding the match=word attribute to the listings shortcode to perform a word match. Example usage:
[jreviews type="listings" custom_params="keywords=you" match="word" limit="3"]The above will match "you", but not "yourself", "yours", etc.