Perhaps you should try some spelling variations:
thanh thong » thanh thuong, thanh hong, thanh thang
chieu sang » chieu sach, chieu xanh, hieu lang
dung cong » dung trong
hieu van » hieu va, thien van, lieu va
thong tu » phong tuc, thong tin, thong ke
tu dung » tuc dung, tu duong, su dung
ty dan » ty dau, ty van, ky dan

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc ((chieu sang) OR (hieu van)) - thanh thong tu dung cong ty dan ca~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc ((chieu sang) OR (hieu van)) - thanh thong tu dung cong ty dan ca".
• Adding a wildcard symbol may retrieve word variants: doc ((chieu sang) OR (hieu van)) - thanh thong tu dung cong ty dan ca*.