Complex sentence: Many countries in Southeast Asia, such as Vietnam, use condensed milk to flavor their coffee; in Malaysia, "teh tarik" is made from tea mixed with condensed milk; and condensed milk is an integral element in Hong Kong tea culture.
Split into simpler sentences: Many countries in Southeast Asia, such as Vietnam, use condensed milk to flavor their coffee. In Malaysia, "teh tarik" is made from tea mixed with condensed milk, and condensed milk is an integral element in Hong Kong tea culture.