Perhaps you should try some spelling variations:
cang thang » cong thanh, dang thanh
chieu sang » chieu sach, chieu xanh, hieu lang
hieu manh » chieu xanh, hieu nganh, dieu hanh
hang cong » dang cong, hang nong, bang cong
thang va » hang va, trang va, thong va
cong tap » cuong tap, cong tac, cong tan
toan cau » toan cao, toan ban, toan tai
toan tap » toan ban
va hang » van hang, va nang, va lang

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)) - cang thang va hang cong tap ((toan cau) OR (toan tap))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((chieu sang) OR (hieu manh)) - cang thang va hang cong tap ((toan cau) OR (toan tap)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((chieu sang) or (hieu manh)) - cang thang va hang cong tap ((toan cau) OR (toan tap))".
• Adding a wildcard symbol may retrieve word variants: hoc ((chieu sang) or (hieu manh)) - cang thang va hang cong tap ((toan cau) OR (toan tap))*.