Perhaps you should try some spelling variations:
hanh trong » hanh trang, anh trong, hinh trong
chieu xanh » chieu sach, chieu sang, chieu tinh
hieu lang » chieu sang, hieu quang, nhieu tang
chua dong » cua dong, ha dong, huy dong
cua dung » cua dang, cua dong, qua dung
cong dan » cong san, cong tan, huong dan
dan toan » van toan, dan than, manh 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 ((hieu lang) or (chieu xanh)) - hanh trong ((cua dung) or (chua dong)) cong dan toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hieu lang) OR (chieu xanh)) - hanh trong ((cua dung) OR (chua dong)) cong dan toan cau.
• Adding a wildcard symbol may retrieve word variants: hoc ((hieu lang) or (chieu xanh)) - hanh trong ((cua dung) or (chua dong)) cong dan toan cau*.