There are 2 repositories under query-understanding topic.
Awesome Search - this is all about the (e-commerce, but not only) search and its awesomeness
Systematic Review Query Visualisation and Understanding Interface
IntentsKB: A Knowledge Base of Entity-Oriented Search Intents - CIKM'18
Towards an Understanding of Entity-Oriented Search Intents - ECIR'18
Presentation and Code for talk at Conferences - MLDS-2020 and DHS-2019
Target Type Identification for Entity-Bearing Queries - SIGIR'17