I just found out this is a combination of 2 songs. I've been listening to his performance a long time, and I got curious. I used to think "Baby Dos Vidanya" was a Russian song and then he had someone write new Chinese lyrics for part of it, for this arrangement. But Baby Dos Vidanya is a Chinese song by Pu Shu. He performs that part very similar to the original. The Russian part of the performance is from "Oh, Viburnum's Blooming" (lyrics by a Soviet poet Mikhail Isakovsky, and then music was written for it). It was performed as a song in the movie Cossacks of the Kuban from 1950. Zhou Shen studied music at a university in Ukraine, which is probablyyy where he may have seen that film, or heard the song, and why he probably is adept at singing in Russian (and Ukrainian!)