1. A method comprising: receiving a query image that was submitted by a client device; obtaining, by one or more processors, a set of text labels associated with the query image from a database of text labels associated with images, each text label associated with a confidence score specifying a measure of confidence that the text label accurately describes a topic of the image; identifying, from the set of text labels, a first text label having a highest confidence score among the set of text labels associated with the query image and a second text label having a confidence score that meets a confidence score threshold, the second text label being different from the first text label; obtaining, by one or more processors and based on the query image, a search result that identifies a web page including an image that matches the query image; comparing text from the web page identified by the search result with the first text label that was identified from the set of text labels associated with the query image; determining, by one or more processors and based on the comparison, that the text included in the web page matches the first text label that was identified from the set of text labels associated with the query image; and providing, to the client device and in response to determining that the text matches the first text label, the second text label for presentation at the user device as an alternative query related to the search result.