Perhaps you should try some spelling variations:
thanh trung » thanh tung
thiet tach » chiet tach, thuat tach
thien hach » thien thanh, hien hanh
thong cong » trong cong, tong cong, thong thong
trung cua » truong cua, trung tuan, trung cap
cua thong » cua thuong, cua khong, cua tong
cong toan » cong tan, cong hoan, cong tuan
phan cau » phan cac, phan tu, phan lap
phan dau » phan tu, hang dau

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

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