Perhaps you should try some spelling variations:
thieu sang » chieu sang, thieu khang, thieu quang
hieu lang » chieu sang, hieu quang, nhieu tang
thong dan » tuong dan, thong den, trong dan
thong van » trong van, thong va, thong quan
thanh ban » thanh san, thanh van, thanh bac
tranh va » tranh van, trang va, trinh va
va thong » va thuong, va phuong, he thong

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