The London club have kept just one clean sheet in six league games this campaign.
"Every weekend at the moment we having to come back and score. We did it at Leicester (League Cup) but against Arsenal, who were playing at home, it was not possible," Hazard told the Chelsea website (www.chelseafc.com).
"There are no excuses (for Arsenal defeat). It was not good. We lost too many duels."
Chelsea, without a win in their last three league games, are eighth in the standings, eight points adrift of leaders Manchester City. They face champions Leicester City and Manchester United in two of their next three games.
"We need to be better. In the last three games in the league there have been nine points available and we have got one. It is disappointing," Belgian Hazard said.
"We need to go away and work on what we are doing wrong ahead of the big matches that are coming up."
Chelsea travel to Hull City on Saturday.
(Reporting by Nivedita Shankar in Bengaluru, editing by Ed Osmond)
