1. A method comprising: receiving an initial query; identifying one or more additional queries related to the initial query; determining a respective utility measure for each of the one or more additional queries, wherein the utility measure represents a likelihood that an additional query would be a final query in a series of query refinements from the initial query issued in a query session; selecting an additional query from the one or more identified additional queries having a highest utility measure among the one or more identified additional queries; identifying one or more content items for the selected additional query; generating a content block comprising one or more content items identified for the selected additional query; and providing the content block to a client device to be displayed along with search results associated with the initial query.