Perhaps you should try some spelling variations:
chieu xanh » chieu sach, chieu sang, chieu tinh
hanh trung » thanh trung, manh trung, danh trung
hanh trang » thanh trung, canh tranh, hanh trinh
hieu lang » chieu sang, hieu quang, nhieu tang
ban cong » bang cong, van cong, phan cong
cong bai » cuong bai, cong hai, cung bai
bai toan » bai tap
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: theo ((chieu xanh) or (hieu lang)) - ((hanh trung) OR (hanh trang)) cua ban cong bai toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo ((chieu xanh) OR (hieu lang)) - ((hanh trung) OR (hanh trang)) cua ban cong bai toan cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo ((chieu xanh) or (hieu lang)) - ((hanh trung) OR (hanh trang)) cua ban cong bai toan cao".
• Adding a wildcard symbol may retrieve word variants: theo ((chieu xanh) or (hieu lang)) - ((hanh trung) OR (hanh trang)) cua ban cong bai toan cao*.