Unlike oily skin that has excessive oil levels, your skin doesn’t have enough oil to keep itself healthy.
To treat dry skin, it’s a given that you need to hydrate and nourish more than anything else. Serums and ampoules are a great help when you need an extra boost of nutrition. To follow, you also need to incorporate rich moisturisers or facial oils with fatty acids to lock in the hydrating agents of your serums or ampoules. Facial oils, in particular, can help a lot in strengthening your skin barriers which is what your skin is lacking. (p.s. avoid hot showers!)