Systems and methods are provided for document searching. In one implementation, a computer-implemented method provides keyword searching. The method may receive a plurality of noisy keywords for a document collection. A server may generate tokens for a plurality of keywords in the document collection and merge the tokens to create an index. A search query may be received. The search query may include at least one search phrase. For the at least one search phrase, an indication may be received from a user specifying to perform one of a noisy phrase search or a noiseless phrase search. The method may search the index for the at least one search phrase based on the indication received from the user.