You will not find many used BMW and Audi cars (hatchbacks) in India because very few were ever sold.
BMW did offer the 1 Series hatchback for a short time, but the numbers were still limited.

Instead, it’s better to explore their small SUVs like the Audi Q3 and the BMW X1. If you are open to Mercedes-Benz cars, you can also check the A-Class or B-Class hatchbacks, though these too are rare, or consider the Mercedes GLA. 

When buying a premium used car, though, make sure you buy from the brand itself, as they all have an approved used program. You can also buy one from a very reputable reseller, and if things go wrong, it can be very expensive to fix.