The Melbourne fare is actually around $70 cheaper than a direct flight to Kuala Lumpur (scratches head). Anyway, heaps of seats and dates available for travel Aug-Nov & Jan-May. I've left Sydney and Gold Coast off as they're over $100 more expensive. And below are the usual screenshots. Enjoy :)
Ho Chi Minh City ex Perth $288
Ho Chi Minh City ex Melbourne $364
How about Sydney ???!@#!@#