The Blues have kept just one clean sheet this season, which came in their 3-0 win over Burnley before the international break.
"We have had three games, three wins [before the draw with Swansea]," Hazard said.
"We played some good stuff. We scored goals. But also conceded them.
"Apart from before the international break [in their 3-0 win over Burnley], we have conceded goals.
"We have always conceded one or two goals, which is a shame.
"It's up to us to work harder defensively, to be more solid, and to score more goals to put on more of a show and win matches."