15. A non-transitory machine-readable medium embodying a set of instructions that, when executed by a processor, cause the processor to perform operations, the operations comprising: receiving a first initial search query from a first user, the first initial search query comprising at least one search operator and at least one search term; generating a first rewritten search query based on the first initial search query, the generating the first rewritten search query comprising rewriting at least one optional search operator in the first initial search query using at least one required search operator and at least one exclusion search operator in response to a determination that the first initial search query comprises the at least one optional search operator and does not comprise any required search operators; generating a first set of search results for the first rewritten search query; and causing the first set of search results to be presented to the first user.
19. The non-transitory machine-readable medium of claim 15 , wherein the operations further comprise: receiving a second initial search query from a second user, the second initial search query comprising at least one search operator and at least one search term; generating a second rewritten search query based on the second initial search query, the generating the second rewritten search query comprising maintaining all required clauses and exclusion clauses from the second initial search query in the second rewritten search query and removing all optional clauses in the second initial search query from the second rewritten search query in response to a determination that the second initial search query comprises at least one required search operator; generating a second set of search results for the second rewritten search query; and causing the second set of search results to be presented to the second user.