A method includes receiving data characterizing historical user interaction with a search engine associated with a plurality of items, the received data including a first search query and a first item name selected by a user in response to receiving a result of a search of the first search query; training, using the received data, a model that maps item names to referring expressions, the training including using the first item name selected by the user as an input to the model and the first search query as a supervisory signal to the model; and providing the model. Related apparatus, systems, techniques, and articles are also described.