Perhaps you should try some spelling variations:
thanh trung » thanh tung
hieu nganh » vien nganh, hieu manh, nghiep nganh
cua thuong » cua truong, cua phuong, ca thuong
hiem ngan » kim ngan, viem gan
cua thong » cua khong, cua tong, suat thong
cong dan » cong san, cong tan, huong dan
dan than » dan chan, ban than, van than
than cau » toan cau, phan cau, than cap

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((hieu nganh) or (hiem ngan)) - thanh trung ((cua thong) OR (cua thuong)) cong dan than cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hieu nganh) OR (hiem ngan)) - thanh trung ((cua thong) OR (cua thuong)) cong dan than cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hieu nganh) or (hiem ngan)) - thanh trung ((cua thong) OR (cua thuong)) cong dan than cau".
• Adding a wildcard symbol may retrieve word variants: hoc ((hieu nganh) or (hiem ngan)) - thanh trung ((cua thong) OR (cua thuong)) cong dan than cau*.