Perhaps you should try some spelling variations:
chieu sang » chieu sach, chieu xanh, hieu lang
hieu quang » thieu quang, hieu quan, hieu qua
nhanh lang » nhanh quang, nhanh thang, nhanh dong
thong than » thong thanh, thong phan, thong nhan
nhan dang » nhan dan, phan dang, tran dang
cua thong » cua thuong, cua khong, cua tong
than toan » thanh toan, than tuan, thuat toan
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)) - ((nhanh lang) OR (nhan dang)) 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)) - ((nhanh lang) OR (nhan dang)) cua thong thong than toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((chieu sang) or (hieu quang)) - ((nhanh lang) OR (nhan dang)) cua thong thong than toan cau".
• Adding a wildcard symbol may retrieve word variants: hoc ((chieu sang) or (hieu quang)) - ((nhanh lang) OR (nhan dang)) cua thong thong than toan cau*.