Perhaps you should try some spelling variations:
thanh thong » thanh thuong, thanh hong, thanh thang
dung phuong » dung thuong, bang phuong, dung chung
chieu sang » chieu sach, chieu xanh, hieu lang
phuong tac » phuong tay, phuong bac, huong tac
hieu van » hieu va, thien van, lieu va
thong tu » phong tuc, thong tin, thong ke
tu dung » tuc dung, tu duong, su dung
tac dan » tac danh, cac dan, tac da

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 phuong tac dan ca~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc ((chieu sang) OR (hieu van)) - thanh thong tu dung phuong tac dan ca.
• Adding a wildcard symbol may retrieve word variants: doc ((chieu sang) or (hieu van)) - thanh thong tu dung phuong tac dan ca*.