I may have slightly misremembered. I can't find it in their officially documented APIs either. However if you inspect your network traffic while doing a search

I may have slightly misremembered. I can't find it in their officially documented APIs either. However if you inspect your network traffic while doing a search on their "Find locations" page, it's not too hard to find the address of their REST API. However since it's not documented it might be rude to hit it too hard