No, I can't really explain in details why, since I'm not a French teacher or grammarian trained to do so, but there's no such 'voyons vous'. It would be something like 'voyons pour vous, voyons à votre sujet, à votre propos' , or 'nous allons voir pour vous'.

The right translation for what you wanted to say to LVB would be, I guess : 'voyons comment tu parles ou écris en Français'. I think it's pretty easy.

CRC