1. A method comprising: receiving, using one or more processors, a search query; identifying, using the one or more processors, a plurality of entities referred to in the search query, wherein each of the entities is associated with an entity ID uniquely assigned to the particular entity; generating, using the search query, a search query graph that comprises: a) the search query; b) for each of the plurality of entities, the entity ID uniquely assigned to the particular entity; c) for each of the plurality of entities, one or more properties of the particular entity, wherein the one or more properties comprise one or more other entities; and d) one or more relationship connections between the plurality of entities and the one or more properties; based on the search query, identifying one or more candidate content selection criteria graphs from a database using the search query, wherein each of the candidate content selection criteria graphs relates to one or more of the identified entities referred to in the search query, wherein the one or more candidate content selection criteria graphs are associated with one or more content items; identifying, from the one or more candidate content selection criteria graphs, a particular content selection criteria graph that matches the search query graph based, at least in part, on a similarity between the one or more entities, one or more properties, and one or more relationship connections of the search query graph and the particular content selection criteria graph, wherein identifying a particular content selection criteria graph comprises comparing entity confidence scores of the search query graph with threshold confidence scores of the one or more candidate content selection criteria graphs; identifying content items associated with the particular content selection criteria graph that are distributed using the particular content selection criteria graph; and providing, for display on a computing device that submitted the search query, one or more of the identified content items.