Perhaps you should try some spelling variations:
hanh trung » thanh trung, hanh trang, manh trung
chieu sang » chieu sach, chieu xanh, nhieu tang
hieu lang » hieu quang, nhieu tang, hieu van
cong manh » cong danh, duong manh, cong thanh
manh toan » thanh toan, anh tuan, tinh toan
cua hang » cua dang, cua nhung, cua ban
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 lang)) - hanh trung ((cua hang) or (cua cong)) cong manh toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((chieu sang) OR (hieu lang)) - hanh trung ((cua hang) OR (cua cong)) cong manh toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((chieu sang) OR (hieu lang)) - hanh trung ((cua hang) or (cua cong)) cong manh toan cau".
• Adding a wildcard symbol may retrieve word variants: hoc ((chieu sang) OR (hieu lang)) - hanh trung ((cua hang) or (cua cong)) cong manh toan cau*.