As already mentioned by rotanes - the only Star Alliance Flight to Da Nang airport is with Asiana Airlines. So if you want to book the whole itinerary with your miles you first have to get to Seoul. As there are no direct flights from Zurich to Seoul you have to fly via FRA / MUC / IST.
Another way to get there would be flying LX ZRH-BKK and then TG to Hanoi or Ho Chi Minh City - from where you can get a separate Ticket with Vietnam Airlines or Jetstar to Da Nang