Perhaps you should try some spelling variations:
thiet tach » chiet tach, thien hach, thuat tach
thong cong » trong cong, thong thong, phong chong
hoc thiet » hoc thieu, hoc thuyet, hoc hien
trung cua » truong cua, trung tuan, dung cua
trung cap » truong cao, trung tam
tong cong » trong cong, cong cong, dung cong
doan phan » doanh phan, toan phan, dan phan
phan cau » phan dau, phan cac, phan tu

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