ASG and uniform EC2 distribution issue

I setup the following environment 1x IGW 1x ALB, 1x ASG, 2x Public Subnets, 1 x Private Subnet. The private subnets do not have internet access yet. I attached the 3 subnets to the ASG, but I only attached the 2x public ones to the ALB. I set the min and desire capacity = 3 on the ASG. The reason why is because I was expecting to see that the ASG place 1x EC2 on each subnet. Well I was wrong :-(!. So I tried to increase the min and desire capacity = 7 and about the same, the autoscaling place them all over.

Is there anyway to to tell the ASG to place at least x number of EC2 on each subnet?