Perhaps you should try some spelling variations:
thanh trung » thanh tung
chieu sang » chieu sach, chieu xanh, hieu lang
hieu quang » thieu quang, hieu quan, diep quang
dang cong » dung cong
cong manh » cong danh, duong manh, cong thanh
manh toan » thanh toan, anh tuan, tinh toan
trung va » truong va, trang va, trung ha
toan cau » toan cao, toan ban, toan tap
va dang » van dang, va nang, va lang

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

• Performing a fuzzy search may retrieve terms with similar spellings: ho ((chieu sang) or (((hieu quang) or (hieu qua)))) - thanh trung va dang cong manh toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho ((chieu sang) OR (((hieu quang) OR (hieu qua)))) - thanh trung va dang cong manh toan cau.
• Adding a wildcard symbol may retrieve word variants: ho ((chieu sang) or (((hieu quang) or (hieu qua)))) - thanh trung va dang cong manh toan cau*.