Perhaps you should try some spelling variations:
hieu quang » thieu quang, hieu quan, hieu qua
nhieu tang » chieu sang, hieu lang, nhiet nang
canh trinh » canh tranh, hanh trinh, canh tinh
song manh » song hanh, song minh, song xanh
manh toan » thanh toan, anh tuan, tinh toan
trinh va » trinh van, trinh vat, trinh ve
toan cau » toan cao, toan ban, toan tap
va nang » van nang, da nang, cam nang

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 quang) or (nhieu tang)) - canh trinh va nang song manh toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc ((hieu quang) OR (nhieu tang)) - canh trinh va nang song manh toan cau*.