Perhaps you should try some spelling variations:
thanh trung » thanh tung
nang thanh » dang thanh, tang thanh, nhanh thanh
hoc thieu » toc thieu, hoc hien
cong nang » cong ngang, cong lang, cong nong
doc hieu » toc thieu, hoc hien
thanh tu » hanh tu, nhanh tu, thanh tung
va bang » va lang, va ban, va hang
va nang » van nang, da nang, cam nang

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((doc hieu) or (hoc thieu)) xanh - thanh trung ((va bang) OR (va nang)) cong nang thanh tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((doc hieu) OR (hoc thieu)) xanh - thanh trung ((va bang) OR (va nang)) cong nang thanh tu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((doc hieu) or (hoc thieu)) xanh - thanh trung ((va bang) OR (va nang)) cong nang thanh tu".
• Adding a wildcard symbol may retrieve word variants: ((doc hieu) or (hoc thieu)) xanh - thanh trung ((va bang) OR (va nang)) cong nang thanh tu*.