Perhaps you should try some spelling variations:
thanh trung » thanh tung
hoc thiet » hoc thieu, hoc thuyet, hoc hien
trung cua » truong cua, trung tuan, trung cap
so thiet » soc thiet, hoa thiet, tao thiet
tong tac » tuong tac, trong tac, cong tac
tac phan » tac pham, tai phan, tac phat
cua han » cua hang, cua nhan, cua phan

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) or (so thiet)) tach - thanh trung cua han tong tac phan tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((hoc thiet) OR (so thiet)) tach - thanh trung cua han tong tac phan tu.
• Adding a wildcard symbol may retrieve word variants: ((hoc thiet) or (so thiet)) tach - thanh trung cua han tong tac phan tu*.