Perhaps you should try some spelling variations:
thiet hach » thien hach, thuyet hach, thiet hai
hanh tranh » canh tranh, hanh trinh, hanh trang
nhung cong » dung cong, thong cong, hang cong
hoc thiet » hoc thieu, hoc thuyet, hoc hien
tranh van » tran van, trinh van, thanh van
van nhung » van nhuong, va nhung, van hung
ban than » ban thanh, van thanh, ban hang
ban hanh » ban hang

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 hach - hanh tranh van nhung cong ((ban than) OR (ban hanh)) cau~.
• Adding a wildcard symbol may retrieve word variants: hoc thiet hach - hanh tranh van nhung cong ((ban than) or (ban hanh)) cau*.