Perhaps you should try some spelling variations:
doanh quang » doan quang, doanh quan, doanh luan
chieu sang » chieu sach, chieu xanh, nhieu tang
quang hung » quang dung, quang phuong, quang trung
hieu lang » hieu quang, nhieu tang, hieu van
hung cong » nhung cong, hung cuong, phung cong
cong ban » cong bang, cong san, cong tan
ban nhan » ban than, van nhan, ban thanh
nhan cay » nhanh cay, nham cay, nhan cach

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((hieu lang) or (chieu sang)) - toan doanh quang hung cong ban nhan cay~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hieu lang) OR (chieu sang)) - toan doanh quang hung cong ban nhan cay.
• Adding a wildcard symbol may retrieve word variants: hoc ((hieu lang) or (chieu sang)) - toan doanh quang hung cong ban nhan cay*.