Perhaps you should try some spelling variations:
thanh trung » thanh tung
nang thanh » dang thanh, tang thanh, nhanh thanh
hieu xanh » chieu xanh, hieu nganh, dieu hanh
hieu manh » chieu xanh, hieu nganh, dieu hanh
trung van » truong van, trong van, trung va
hang cong » hang nong, bang cong, thanh cong
dang cong » dung cong
thanh tu » hanh tu, nhanh tu, thanh tung

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 xanh) or (hieu manh)) - thanh trung van ((hang cong) OR (dang cong)) nang thanh tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc ((hieu xanh) OR (hieu manh)) - thanh trung van ((hang cong) OR (dang cong)) nang thanh tu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc ((hieu xanh) or (hieu manh)) - thanh trung van ((hang cong) OR (dang cong)) nang thanh tu".
• Adding a wildcard symbol may retrieve word variants: doc ((hieu xanh) or (hieu manh)) - thanh trung van ((hang cong) OR (dang cong)) nang thanh tu*.