My grandma is 103 years old and she has skin

Patient: My grandma is 103 years old and she has skin rash due to old age. She’s gone to skin specialists and dermatologists but none of their prescriptions worked. One day my mom gave her cetaphil and it worked for a short while ( still not strong enough ). My grandma’ skin is very thin and she has a trouble producing enough moisture under her skin. Could you recommend a better skin care products that will relief her itchy skin? She’s alsoTried to bath less and rub olive oil on her skin, but she still feels itchy especially on her scalp, arm and thigh. Thank you for your help

Symptoms: Itchy skin on arms, scalp, thigh, and belly

Doctor: