You can't blame them, they have been spoon-fed since young. For them, living in Australia will be 'bad' because they have to do everything themselves. No mummy, no maid, no daddy's money, they really have to be independent. They are too used to the Singapore nanny system, government does everything for you, govt protects women with law without them laying a finger, government gives out cash divdends to you and more. Not like Australia, you might have to build your own house, searching for houses not as easy as searching for HDB and the MP in Australia is never going to entertain the requests of placing in good school or any others. Naturally, they left. Only the tough and independent nuts stay and eke out a living.
For the Koreans, it is a different story. They have been brought up since young to have the 'Koreans are superior' mindset, not unlike how some of the Japanese are taught. So when these Koreans move over to Australia, they still keep their mindset that 'Koreans are supreme' and hence only stick with their own kind. Even saw one of my friend's Korean friend, despite being educated in America since 15, still wearing tees and posting on Facebook shouting out loud about Korean pride. Sad to see that these Koreans have never fully integrated, only a minority integrated. Coupled with how they speak loudly in public and their habit of shoving past people, no wonder they are one group that is not well-liked, but higher than the Arabs for sure.
The Vietnamese are like the Koreans, only stick to themselves and never bothering to mix with the locals. Coupled with how some of them are snakeheads in the drug trade, they are also seen as less than desirable.
The mainlanders are slightly more open to mixing with the locals and I notice among the four groups of people mentioned in this post, some of the women managed to marry locals. :o