Perhaps you should try some spelling variations:
thanh trung » thanh tung
thiet hach » thien hach, thuyet hach, thiet hai
nhung cong » dung cong, thong cong, nhung don
hoc thiet » hoc thieu, hoc thuyet, hoc hien
trung cua » truong cua, trung tuan, trung cap
hang cong » dang cong, hang nong, thanh cong
bang cong » dang cong, bang song, dung cong
doan phan » doanh phan, toan phan, dan 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 hach - thanh trung cua ((nhung cong) or (((hang cong) OR (bang cong)))) doan phan tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thiet hach - thanh trung cua ((nhung cong) OR (((hang cong) OR (bang cong)))) doan phan tu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc thiet hach - thanh trung cua ((nhung cong) or (((hang cong) OR (bang cong)))) doan phan tu".
• Adding a wildcard symbol may retrieve word variants: hoc thiet hach - thanh trung cua ((nhung cong) or (((hang cong) OR (bang cong)))) doan phan tu*.