The Villans, who are eight points above the relegation zone, have conceded eight goals in their last two games.
Bertrand now hopes that they can tighten up at the back and rediscover the form that has seen them keep eight clean sheets this term.
"It is never good to concede eight goals in two goals - it should never happen," the 24-year-old told the club's official website. "But we are just focusing on winning the next few games.
"We realise as a defence that if we can keep things tight then it will go a long way to us getting the points that we need."
Villa return to action on Saturday when they entertain bottom-placed Fulham.