Perhaps you should try some spelling variations:
chieu sang » chieu sach, chieu xanh, hieu lang
hieu quang » thieu quang, hieu quan, hieu qua
thong than » thong thanh, thong phan, thong nhan
hanh mang » nhanh mang, hanh trang, nhanh lang
cua thong » cua thuong, cua khong, cua tong
than toan » thanh toan, than tuan, thuat toan
mang cua » manh cua, dung cua, ban cua
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 mang cua thong thong than toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((chieu sang) OR (hieu quang)) - hanh mang cua thong thong than toan cau.
• Adding a wildcard symbol may retrieve word variants: hoc ((chieu sang) or (hieu quang)) - hanh mang cua thong thong than toan cau*.