Perhaps you should try some spelling variations:
cong thanh » dong thanh, cong trinh, cong tan
bien tinh » bi tinh, yen tinh, diep tinh
tranh cua » doanh cua, manh cua
hoc bien » hoc hien, hoc vien, hoa bien
cong dan » cong san, cong tan, huong dan
toan cau » toan cao, toan ban, toan tap
ban cua » ban quan

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: hoc bien tinh - canh ((tranh cua) or (ban cua)) nhung ((cong dan) or (cong thanh)) toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc bien tinh - canh ((tranh cua) OR (ban cua)) nhung ((cong dan) OR (cong thanh)) toan cau.
• Adding a wildcard symbol may retrieve word variants: hoc bien tinh - canh ((tranh cua) or (ban cua)) nhung ((cong dan) or (cong thanh)) toan cau*.