If you have a legitimate Russian copy (published by Snowball), it will only have a serial for registration with them; they will provide the Russian-language updates. For exact details about where it is located in the packaging you'd need to contact Snowball.

More likely though, if you bought it off Ebay and it was labelled on the auction as a 'foreign version, but plays in english' game, then you're the victim of a bootlegger. Since it's a fake copy, it won't have a valid serial at all. In that case you'd need to pursue the matter with Ebay to get your money back and purchase a legitimate copy.