Perhaps you should try some spelling variations:
thanh trung » thanh tung
thong cong » trong cong, tong cong, thong thong
hoc thiet » hoc thieu, hoc thuyet, toc thieu
trung cua » truong cua, trung tuan, trung cap
cua thong » cua thuong, cua khong, cua tong
cong tan » cong tac, cong san, cong thanh
phan cau » phan dau, phan cac, phan lap

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

• If you are trying to use Boolean operators, they must be ALL CAPS: ((hoc thiet) OR (hoc hien)) anh - thanh trung cua thong cong tan ((phan cau) OR (phan tu))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((hoc thiet) or (hoc hien)) anh - thanh trung cua thong cong tan ((phan cau) OR (phan tu))~".
• Adding a wildcard symbol may retrieve word variants: ((hoc thiet) or (hoc hien)) anh - thanh trung cua thong cong tan ((phan cau) OR (phan tu))*.