Perhaps you should try some spelling variations:
chieu sang » chieu sach, chieu xanh, hieu lang
thanh tran » thanh trang, thanh toan, thanh tra
thong cong » tong cong, thong thong, phong chong
hieu manh » chieu xanh, hieu nganh, dieu hanh
van toan » van tuan, van tan, van thanh
toan tap » toan ban
tran va » tran van, trang va, tranh va

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((chieu sang) or (hieu manh)) - thanh tran va ((thong cong) OR (trong cong)) van toan tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((chieu sang) OR (hieu manh)) - thanh tran va ((thong cong) OR (trong cong)) van toan tap.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((chieu sang) or (hieu manh)) - thanh tran va ((thong cong) OR (trong cong)) van toan tap".
• Adding a wildcard symbol may retrieve word variants: hoc ((chieu sang) or (hieu manh)) - thanh tran va ((thong cong) OR (trong cong)) van toan tap*.