Stalling at low acceleration and shutting off in reverse at low acceleration

I recently bought the truck above and noticed a problem when I test drove it. At idle the truck runs beautiful and when you put it in drive or reverse it’s fine but at low acceleration in drive it will stutter and sound like it’s going to shut off but won’t and it drives fine going down the road or at WOT. When you put it in reverse and accelerate slowly it sounds the same as drive but it will stall out and shut off unless you floor it in reverse.