They look fine. Both flights do operate to and from Don Mueang.
Looks like total fares are 1500baht per sector so 3000baht (about 70Euros) Chang Mai-Phuket.
Clever the way the add-ons turn the 808.41baht fare into a perfect 1500
1 Fare (ADULT) THB 808.41
1 Tax, Fee and Surcharge (ADULT) THB 691.59
Airport Tax THB 100.00
Insurance THB 50.00
Administration Fee THB 50.00
Fuel Surcharge THB 400.00
VAT THB 91.59
Total (ADULT) THB 1,500.00
I've used NOK a few times. They have a nice touch of lining up the stewardesses at the front of the cabin and introducing them individually by name to you. They have some real beauties too.