Perhaps you should try some spelling variations:
thien hach » thien thanh, hien hanh
hoc thien » hoc hien, hoc thieu, hoc thiet
hanh hang » thanh hang, hang hang, hanh han
va phuong » va thuong, cac phuong
thanh nga » thanh ngu, thanh nhan, nhanh ngan
cong van » cong vang, song van, cong tan
cong san » cong tac

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: hoc thien hach - hanh hang va phuong ((cong van) or (cong san)) thanh nga~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thien hach - hanh hang va phuong ((cong van) OR (cong san)) thanh nga.
• Adding a wildcard symbol may retrieve word variants: hoc thien hach - hanh hang va phuong ((cong van) or (cong san)) thanh nga*.