Villas-Boas told Sky Sports News: "He had a good couple of chances, and for you to have chances you have to position yourself to have those good chances and he was there present. With a little bit more luck he will find the back of the net.
"I think we are in the top three for teams creating goalscoring chances, it's just finding that efficiency. It's been happening all season.
Chelsea are currently fourth in the Premier League.