Perhaps you should try some spelling variations:
thanh dung » thanh duong, thanh tung, thanh hung
hieu sang » chieu sang, hieu lang, hieu quang
trong san » trong cac, cong san, dong san
doc hieu » toc thieu, hoc thieu, hoc hien
cua dung » cua dang, qua dung, cua rung
cua dong » chua dong, cua cong, cua dang
san phan » san pham, van phan, sat phan
phan cac » nhan cach, phan dau, phan lap

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc hieu sang - thanh dung ((cua dung) or (cua dong)) trong san phan cac~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc hieu sang - thanh dung ((cua dung) OR (cua dong)) trong san phan cac.
• Adding a wildcard symbol may retrieve word variants: doc hieu sang - thanh dung ((cua dung) or (cua dong)) trong san phan cac*.