Hello,
Dry skin results when there is not enough water in the stratum corneum for it to function properly. Too much soapy water, exposure to harsh chemicals, the normal aging process and certain types of skin diseases are some of the causes of decreased amounts of protective skin oils which in turn causes dry skin.
The mainstay of management is liberal use of moisturizers after washing with luke warm water. Soap should be used minimally. Moisturizers should be reapplied liberally during the day. You can also use a topical cortisone (steroid) cream or ointment like dermacort(hydrocortisone) for some days. Adding a humidifier to the central heating system of your home or using a humidifier also helps.
It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your doctor. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.
I'm not a doctor but bars of soaps like dove are usally quite drying, i would suggest trying glycerin soap or putting extra virgin olive oil in you bath(oil bath) you will leave the bath having fully moisturised skin, for you hair buy glycerin not sure which country your in but you can purchase this from the pharmacy or chemist if you have like a empty bottle or container (like 250ml ) empty half the glyrcerin into the bottle and match the same quantity with water may so somewhere around 40% glycerin and 60% water should be fine, apply this mixture to your hair at night, or if you prefer to use gel like products purchase the aloe vera gel from holland and barrets and replace the water with the gel and apply the glycerin and aloe vera gel to the dry parts of your hair in small amounts or how ever much you feel necessary this should solve your dry hair and skin problems, let me know how you get on.