Furniture

Hello, I have old furniture, how to freshen them up (sofas, sofas, armchairs) I can't wash them every week ... you still know how it is with the old people in the village ... they don't keep them very much, the question is different, that I don't know what to rub or spray them with, at least to remove the unpleasant smell from them .... I also have a buffet of soc - massive, very strong, but old and scratched - how can I renew it, would it be good it happened if I covered it with self-adhesive foil or drove it with wood varnish. Thanks for the comments.