If you have any idea about skin then please answer my ques. esp. if your a dermatologist!?

I've been having this skin problem since i was between 7-9 years old i think...me and my parents doesn't even know what it's called because even the doctors that we go to keep saying they don't really know what it is or some dermatologist told me/us that it's something that has to do with hair follicle. It looks like a little rashes that is really visible most of the time but there are times that it's not. It doesn't hurt, it doesn't turn red or anything, etc. so for short, it just looks ugly in my arms and all the way to my back. I've personally seen some people that has this too but does anyone know the name of this thing i'm talking about? is there a cure for this? because the creams that the dermatologists gave me over the years doesn't seem to work at all! =(