You are conflating two distinct legal principles:

Caveat Emptor, the principle that the BUYER of property takes the risk of defects in that property (except in the case of fraud/misrepresentation on the part of the SELLER); and

A thief cannot convey good title, which is actually a fallacy. If you honestly purchase goods from a thief, for market value, without knowing that the goods are stolen, your interest in those goods actually trumps those of the original owner. Counter-intuitive huh?

The original owner has recourse only against the thief, as you are effectively an innocent party to the transaction.

Caveat emptor protects the seller against a careless purchase followed by buyer's remorse.

Merely possessing goods which are stolen is not a crime in any jurisdiction i'm aware of (and for good reason), this offence almost always implies a mental element of knowledge or at least suspicion as to the source of the goods.