The Dutchman has tried a variety of combinations in an attempt to find balance in midfield, but has been forced to play forward Wayne Rooney out of position in order to do so.
Van Gaal insists Rooney is happy to play in midfield but admits he is playing there because “there is no one else”.
“Signing a creative player should be our priority this summer,” the 63-year-old said. “I’m looking for balance and I need it in midfield.
“In the last few games I’ve played Adnan Januzaj and Angel Di Maria in the midfield positions, and you need a certain balance for that kind of creative player.
“Radamel Falcao and Robin van Persie are also creative players so then you have four of them, and you still have to look for balance in your team.
“Wayne is playing in midfield because there is no one else. He’s happy to do so otherwise he should come to me and say he’s not, but he never does. He’s always friendly to me and wants to perform.
“But of course when the whole world is writing that he has to be in the striker’s position then he will be thinking ‘hey, maybe’. He’s human.”
United have inevitably been linked with a string of midfield players since Van Gaal took over, most notably the Dutch international Kevin Strootman of Roma and former United academy graduate Paul Pogba, who is at Juventus.
Pogba’s agent Mino Raiola told Sources last month that he anticipates a fierce bidding war for the France international’s signing this summer and insisted the player is not upset with United for previously letting him go.
Raiola said: “Paul has always said he is not angry with Manchester United – you need to move on.
“There is no personal grudge. On the contrary, he holds Manchester United very dear and has very nice memories there.”