The London side have seen the Community Shield, European Super Cup, World Club Championship, Champions League and Capital One Cup pass them by so far this campaign and currently sit 11 points behind Premier League leaders Manchester United in the Premier League.
And Cech believes that a large portion of the blame can be put down to Chelsea's forwards.
"It was disappointing because we didn't score against Swansea. We knew that we had to score to have a chance to progress, but we didn't and it is a pity," he told reporters.
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"I think we need to be more efficient in front of goal because we are having chances. We have a lot of shots in the game but we need to score more goals than that.
"In the last few games we haven't killed the games off. Against Arsenal it was the same story.
"We had to fight until the end of the game because we didn't take our chances to kill off the game. We need to be more clinical in front of goal."
Chelsea's tie against Brentford in the FA Cup this Sunday will provide the perfect platform for the Blue's strikers to hit top form again, in a competition the side has won in four of the past six seasons.
"We want to keep the record going and we are the defending champions. We would like to defend the trophy," he added.
"We know how hard it is every time, but it is a fantastic competition and we have a lot of player who experienced it for the first time last year and I think it will be the motivation for everyone.
"It is a London derby, it will be a big game for Brentford but we should be ready."