1. A method of suggesting a query for identifying documents in a litigation hold, comprising: receiving a training set of documents, wherein each document in the training set of documents is given a relevance indicator; identifying, by one or more processing devices, properties shared among documents having a similar relevance indicator, and an initial query with one or more initial keywords; determining a spatial proximity between one of the initial keywords and a set of keywords in the training set of documents; generating one or more neighboring queries from the initial query based on the spatial proximity, the neighboring queries including one or more additional queries; receiving a quality score of the neighboring queries, including an indication of a highest ranked neighboring query; repeating the generating one or more neighboring queries and receiving a quality score of the neighboring queries, wherein the highest ranked neighboring query is provided as the initial query, until an indication is received that a quality score of the highest ranked neighboring query is less than a quality score of the initial query, wherein a previously highest ranked neighboring query with a quality score greater than or equal to the quality score of the initial query is a resultant query; and generating a suggested litigation hold query based on the resultant query, wherein the suggested litigation hold query returns documents subject to the litigation hold.