What can i do to my baby's dry itchy and scaly face and scalf?

my baby has very dry skin but its worse on his face and scalf, i have seen the dermatologist with him he recommend using aquos cream as soap and secalia cream i also use oilatum cream and boots baby oil on the scalf. The body got better but his face & scalf is always ruogh and peeling, i keep oiling his hair, creaming the face several times in a day and night but by the time he wakes up it ges tdyer and rugh, pls help its so discomforting for him.