well, we use "vous" or "nous" + verb with all verbs ( the subject vous and nous do the action but the object can be anything example ' vous regardez la télévision'and we use "vous vous" or "nous nous" in when we call " verbes pronominaux" like " se laver" exemple 'vous vous lavez' and here the subject do the action and it's also the object-the first vous is subject and the second one is the object-. hope this can help.