If some Vietnamese do look Chinese it could be the result of the colonisation.
You need to look outside of your Taiwanese view to get a fuller picture, there are people who like to associate themselves with Chinese.Chinese-wannabes.. now that's something new..
The Thais also celebrate Chinese New Year they are not Chinese too.
Singapore's Chinese and Malaysia's Chinese use China's simplified writing system rather than Taiwan's traditional writing system after China made the changed.
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