Perhaps you should try some spelling variations:
thieu khang » chieu khong, thieu quang
thieu sang » chieu sang, thieu quang, hieu lang
thong cong » trong cong, tong cong, thong thong
tranh va » tranh van, trang va, trinh va
va thong » va thuong, va phuong, he thong
cong dan » cong san, cong tan, huong dan

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 (thieu khang)) - canh tranh va thong cong dan ((toan ban) or (van ban))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu sang) OR (thieu khang)) - canh tranh va thong cong dan ((toan ban) OR (van ban)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu sang) OR (thieu khang)) - canh tranh va thong cong dan ((toan ban) or (van ban))".
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu sang) OR (thieu khang)) - canh tranh va thong cong dan ((toan ban) or (van ban))*.