Perhaps you should try some spelling variations:
truong trung » tieng trung
nhung cong » dung cong, thong cong, hang cong
hanh trinh » canh tranh, hanh chinh
hieu lang » chieu sang, hieu quang, nhieu tang
trinh cua » tinh cua, trinh luat, trinh quan
hoi hieu » hoi phieu, hoi tieu, moi hieu
than cap » thanh lap, thanh cac, than cua
khan cap » khan ap, khoan cam, phan cac

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoi hieu lang - hanh trinh cua ((nhung cong) or (truong trung)) dan ((than cap) OR (khan cap))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoi hieu lang - hanh trinh cua ((nhung cong) OR (truong trung)) dan ((than cap) OR (khan cap)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoi hieu lang - hanh trinh cua ((nhung cong) or (truong trung)) dan ((than cap) OR (khan cap))".
• Adding a wildcard symbol may retrieve word variants: hoi hieu lang - hanh trinh cua ((nhung cong) or (truong trung)) dan ((than cap) OR (khan cap))*.