The north London club have already brought in Alexis Sanchez from Barcelona and Mathieu Debuchy from Newcastle, however a striker and a central midfielder are now his key areas to improve on.
Arsenal want to be challenging for the title rather than settling for fourth place and Wenger knows that spending money is the only way to do that.
Sami Khedira is in talks with the Gunners over a proposed move to the Emirates but Wenger knows he already has big competition for places in that area.
“It’s not over, there’s still a long way to go,” Wenger said.
“I can’t give you any names because you’re never sure if you can do what you want, but we’re still out there to strengthen our squad.
“We have big competition in midfield, but we have many players who didn’t play many games last year – Alex Oxlade-Chamberlain, Jack Wilshere, Abou Diaby.
“They’re back now but it’s very difficult to predict how fit they will be at the start of the season.”