To win a match you don't have to dominate it, but you have to take advantage of every opportunity and create as many chances as possible. Chelsea took advantage of their opportunities well despite creating 4 good chances throughout the match. Actually, just 1 goal was enough to make them win the match, but there were still many shortcomings.
This is the fact, even Chelsea since the beginning of the season has been having good ball possession and lots of chances to score But thank God they where able to get a clean sheet and a win.