I've got a Thomas Jones in Glamorgan in the mid-nineteenth century. (Who had a son Thomas Jones who had a son Thomas Jones). I've got him named as the father on a birth certificate but he seems to have died between censuses and identifying his widow and son is hard... lots of Thomas Jones, and Elizabeth Jones.
You don't have it easy, do you.
Where do you start looking, in Russia. Familysearch I guess but where else.