Bringing in that Vietnamese girl's remark might actually reflect on built-in racism of the writer herself. A lot of Chuinese people are somewhat contemptuous fo people from other ethnicities, it is certainly not limited to Vietnamese or necessarily prevalent in that group. It's also possible that that girl's attitude towards Chinese people is akin to that of many Canadians towards Americans - a sense of being vastly outnumbered by a far more powerful neighbour.