Ive noticed when searching for "SERVICE + LOCATION" in google on a phone / table (not yet on desktop) some results will get Site links even though the search query wasn't specifically for them.
Eg. In the below screenshot i searched for "Car rental in London". Notice how Sixt has these site links on their SERP listing.
How can you get these for a site ? Im familiar with seeing them as site links if you search for a brand, but not for a "SERVICE + LOCATION" query.