1. A computer-readable medium storing computer-useable instructions, that when used by a computing device, cause the computing device to perform a method comprising: receiving a search query from an end user at a search engine; determining one or more search results based on the search query; accessing information regarding a plurality of search macros available to the search engine, the plurality of search macros having been previously defined by a plurality of different end users, each search macro comprising a set of user-defined search operators that operate to modify aspects of how searches are performed by the search engine; determining, from the plurality of search macros, one or more search macros relevant to the search query by: performing a search using at least one search macro, receiving one or more search results for the at least one search macro, and comparing at least a portion of the search results for the search query against at least a portion of the search results for the at least one search macro to determine relevance of the at least one search macro for the search query; and communicating an identification of the one or more search macros for presentation to the end user.