Perhaps you should try some spelling variations:
thieu sang » thieu khang, thieu quang, hieu lang
chieu sang » chieu sach, chieu xanh, hieu lang
tinh sinh » tinh ninh, tinh binh, tinh hinh
cong manh » duong manh, cong thanh, hoang manh
cong danh » cuong danh, cong dan, cong thanh
vat hang » van hang, dat hang, va hang
toan ban » van ban

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((thieu sang) or (chieu sang)) - tinh sinh vat hang ((cong manh) OR (cong danh)) toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu sang) OR (chieu sang)) - tinh sinh vat hang ((cong manh) OR (cong danh)) toan ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu sang) or (chieu sang)) - tinh sinh vat hang ((cong manh) OR (cong danh)) toan ban".
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu sang) or (chieu sang)) - tinh sinh vat hang ((cong manh) OR (cong danh)) toan ban*.