Perhaps you should try some spelling variations:
nhung cong » dung cong, thong cong, hang cong
chieu xanh » chieu sach, chieu sang, chieu tinh
hieu lang » chieu sang, hieu quang, nhieu tang
tranh cua » doanh cua, manh cua
cua nhung » va nhung
cong bai » cuong bai, cong hai, cung bai
bai toan » bai tap
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: ho ((chieu xanh) or (hieu lang)) - canh tranh cua nhung cong bai toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho ((chieu xanh) OR (hieu lang)) - canh tranh cua nhung cong bai toan cau.
• Adding a wildcard symbol may retrieve word variants: ho ((chieu xanh) or (hieu lang)) - canh tranh cua nhung cong bai toan cau*.