13. A system for performing a search, the system comprising: one or more processors, one or more memories, one or more computer-readable storage devices, and program instructions stored on at least one of the one or more computer-readable storage devices for execution by at least one of the one or more processors via at least one of the one or more memories, the program instructions comprising: program instructions to receive a search request including a search term; program instructions to determine a plurality of association rules that are each a logical implication that an appearance of the search term follows from an appearance, in a corpus of data, of one or two keywords that are ontologically related to the search term; program instructions to generate a search matrix having a plurality of cells, and having axes labeled with a plurality of keywords that are ontologically related to the search term, wherein at least two cells of the search matrix are associated with respective association rules of the plurality of association rules; program instructions to receive a cell selection that includes multiple cells of the search matrix; program instructions to generate an augmented search string including the search term and, for each cell included in the cell selection, at least one keyword of the association rule of the respectively corresponding cell; and program instructions to perform a search using the augmented search string.
13. A system for performing a search, the system comprising: one or more processors, one or more memories, one or more computer-readable storage devices, and program instructions stored on at least one of the one or more computer-readable storage devices for execution by at least one of the one or more processors via at least one of the one or more memories, the program instructions comprising: program instructions to receive a search request including a search term; program instructions to determine a plurality of association rules that are each a logical implication that an appearance of the search term follows from an appearance, in a corpus of data, of one or two keywords that are ontologically related to the search term; program instructions to generate a search matrix having a plurality of cells, and having axes labeled with a plurality of keywords that are ontologically related to the search term, wherein at least two cells of the search matrix are associated with respective association rules of the plurality of association rules; program instructions to receive a cell selection that includes multiple cells of the search matrix; program instructions to generate an augmented search string including the search term and, for each cell included in the cell selection, at least one keyword of the association rule of the respectively corresponding cell; and program instructions to perform a search using the augmented search string. 14. The system of claim 13 , wherein the cell selection is received from a source of the search request.