Perhaps you should try some spelling variations:
quang thanh » quan thanh, hoang thanh, muong thanh
chieu sang » chieu xanh, hieu lang, nhieu tang
chieu sach » chinh sach, chiet tach, chieu xanh
thanh dang » thanh hang, thanh dan, thanh dong
dang trong » dung trong, dong trong, lang trong
trong ca » trong cac, trong nha
ca van » cac van, cao van, can van

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 (chieu sach)) - tinh quang thanh dang trong ca van ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc ((chieu sang) OR (chieu sach)) - tinh quang thanh dang trong ca van ban.
• Adding a wildcard symbol may retrieve word variants: doc ((chieu sang) or (chieu sach)) - tinh quang thanh dang trong ca van ban*.