The victory took Chelsea to top of Group E on seven points and they need just one more win from their final two games to go through to the qualifying stages.
"From 2-0 we controlled the game and with a few more mistakes from them under pressure, we scored more goals and 5-0 is a good result," Cech told Sky Sports 2.
"We knew it was not going to be easy if the mentality was not right and the mentality was brilliant, that's why we made the game look easy.
"At 5-0 up and controlling the game, we didn't allow them to come into the game and score a goal. It is always important to kill the game off and keep a clean sheet."
Chelsea are back in action on Sunday as they travel to Queens Park Rangers for their Premier League clash.