Perhaps you should try some spelling variations:
nhung cong » dung cong, thong cong, hang cong
chieu tinh » trieu tinh, lieu tinh, chau tinh
hieu manh » chieu xanh, hieu nganh, dieu hanh
tang van » dang van, hoang van, trong van
cong tac » cong ty
tac tren » rac tren, tai tren, tap tren
tren tau » tren thuc, tren may, tren dat
tang va » trang va, thang va, tang vat

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

• Performing a fuzzy search may retrieve terms with similar spellings: theo ((hieu manh) or (chieu tinh)) - hanh ((tang va) OR (tang van)) nhung cong tac tren tau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo ((hieu manh) OR (chieu tinh)) - hanh ((tang va) OR (tang van)) nhung cong tac tren tau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo ((hieu manh) or (chieu tinh)) - hanh ((tang va) OR (tang van)) nhung cong tac tren tau".
• Adding a wildcard symbol may retrieve word variants: theo ((hieu manh) or (chieu tinh)) - hanh ((tang va) OR (tang van)) nhung cong tac tren tau*.