Speaking on BBC Sport, the 39-year-old said: "You know, a striker for Manchester United, when you're not scoring goals, there's a lot of pressure, a lot of people talking about you. Can you do it for Manchester United? I think the best thing to do is simplify it and obviously making the runs into penalty boxes is as easy as it comes, you have to make them runs.
"But simplifying the game, getting the ball, laying it off, getting in the box, getting the ball out wide, getting in the penalty box, putting yourself in the best position to score goals. Nine times out of 10 you're relying on your team-mates to give you chances and put the ball in the box or slide balls in behind."
He added: "Maybe he hasn't been doing that, he hasn't been getting that service of late. But I've got faith in him. I think he is a good player and he works hard. I think that's really important as well. I think he just needs that goal and once he gets it, they'll all start coming."