Saturday's goalless draw with Stoke marked the Saints eight home game without a win. Maurcio Pellegrino's side have fellow relegation battlers Newcastle and Swansea in their next two games.
"You definitely need all the experience you can get and that's what you need to draw on," Bertrand said.
"Everyone needs to stand up and you can't do anything else but look forward because the table is still very tight.
"You're just looking to get that win and string one or two wins together and then it will be a completely different story."