You could talk about:
1. The effect on Vietnam veterans after the war (eg- how they were ignored and secluded by mainstream society).
2. Australian culture: The fleeing of Indochinese refugees brought also changes to our culture (eg- food, languages, communities, shops etc).
3. Refugees- The acceptance of Indochinese refugees, the abolition of White Australia Policy, dififculties integrating into Australian life.
4. Relations with Asia have increased greatly. (eg- trade, tourism)