Perhaps you should try some spelling variations:
thanh trung » thanh tung
hanh trinh » canh tranh, hanh chinh
thong cong » trong cong, tong cong, thong thong
hieu lang » chieu sang, hieu quang, nhieu tang
cua thong » cua thuong, cua khong, cua tong
hoi hieu » hoi phieu, hoi tieu, moi hieu
cong san » cong tac
toan ban » van ban

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 - ((thanh trung) or (hanh trinh)) cua thong cong san ((toan tap) OR (toan ban))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoi hieu lang - ((thanh trung) OR (hanh trinh)) cua thong cong san ((toan tap) OR (toan ban)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoi hieu lang - ((thanh trung) or (hanh trinh)) cua thong cong san ((toan tap) OR (toan ban))".
• Adding a wildcard symbol may retrieve word variants: hoi hieu lang - ((thanh trung) or (hanh trinh)) cua thong cong san ((toan tap) OR (toan ban))*.