Here are the odd ones out for each set:

1. **D. Vietnamese** - The other options (A, B, C) are ethnic groups.
2. **C. blouse** - The other options (A, B, D) are types of traditional clothing.
3. **B. wooden statue** - The other options (A, C, D) are types of traditional houses.
4. **B. sing** - The other options (A, C) are musical instruments.
5. **C. peaceful** - The other options (A, B, D) are related to traditional culture.
6. **C. staircase** - The other options (A, B, D) refer to animals or livestock.
7. **C. unique** - The other options (A, B, D) are actions or processes.
8. **C. ethnic group** - The other options (A, B, D) refer to types of housing or structures.

Let me know if you need further assistance!