Other than candies, especially chocolate ones (made with milk and eggs), which are almost all 'made in china';
Most diary products here in Vietnam, milk and yogurt, are made from 'milk concentre powder' (what ever the heck that is) from New Zealand and Australia.
If you have to worry about any Viet food products, I would worry about fresh vegetables and fruit, which are grown, usually grown with 'human fertilizer' and hosed down with pesticides banned with western countries ... in a country struggling with outbreaks of cholera and acute-diarrhea.