Perhaps you should try some spelling variations:
cong phuong » cong thuong, cong huong, dong phuong
phuong tran » huong tran, phuong trinh, phuong thao
chieu sang » chieu sach, chieu xanh, hieu lang
hieu quang » thieu quang, hieu quan, hieu qua
hanh tang » hanh trang, anh tang, hanh mang
tran toan » tranh toan, tran tuan, tran tan
tang cua » mang cua, hang cua, tang luan
toan cau » toan cao, toan ban, toan tap

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 quang)) - hanh tang cua cong phuong tran toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((chieu sang) OR (hieu quang)) - hanh tang cua cong phuong tran toan cau.
• Adding a wildcard symbol may retrieve word variants: hoc ((chieu sang) or (hieu quang)) - hanh tang cua cong phuong tran toan cau*.