Perhaps you should try some spelling variations:
nhung cong » dung cong, thong cong, hang cong
hieu lang » chieu sang, hieu quang, nhieu tang
tranh cua » doanh cua
cong doan » cong dan, cong hoan, dong doanh
hoc hieu » hoc thieu, hoc hien, doc hieu
manh cua » doanh cua, ban cua
va ban » va bai, va bao

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc hieu lang - canh ((tranh cua) or (manh cua)) nhung cong doan ((va ban) OR (van ban))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hieu lang - canh ((tranh cua) OR (manh cua)) nhung cong doan ((va ban) OR (van ban)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc hieu lang - canh ((tranh cua) or (manh cua)) nhung cong doan ((va ban) OR (van ban))".
• Adding a wildcard symbol may retrieve word variants: hoc hieu lang - canh ((tranh cua) or (manh cua)) nhung cong doan ((va ban) OR (van ban))*.