Perhaps you should try some spelling variations:
thanh trung » thanh tung
chieu sang » chieu sach, chieu xanh, nhieu tang
hieu lang » hieu quang, nhieu tang, hieu van
trung can » trung cap, trung van, trong can
dung cong » dung trong
cong tran » cong tan, cong tuan, cong toan
can dung » chan dung, van dung, dan dung
tran van » luan van

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((chieu sang) or (hieu lang)) - thanh trung can dung cong tran van ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((chieu sang) OR (hieu lang)) - thanh trung can dung cong tran van ban.
• Adding a wildcard symbol may retrieve word variants: hoc ((chieu sang) or (hieu lang)) - thanh trung can dung cong tran van ban*.