I'll just restate what i said on other thread.
--snip--
On purely technical level, it's definitely impossible. But on legal level, there are things you could try such as,
1. Asking log from the server, if you use wallet which connect to single centralized server.
2. If you ever withdraw Bitcoin from centralized exchange to your wallet, you can use withdraw history as proof.
But suing the thief would be costly and take some time, especially if you and the thief live on different country.