Perhaps you should try some spelling variations:
thien van » thi van
ban thanh » ban hanh, ban hang
vu thanh » su thanh, vu khanh, cuu thanh
thanh ky » hanh ky, than ky, thanh tay
hieu van » hieu va, lieu va, hieu ve
va hanh » van hanh, va thanh, va danh
su tien » su kien, su hien, tu tieng
cau tu » dau tu, cau truc
ki su » ky su

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

• Performing a fuzzy search may retrieve terms with similar spellings: vu thanh ky nang x ho. ((hieu van) OR (thien van)) cau tu ((ban thanh) or (va hanh)) ki su tien~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu thanh ky nang x ho. ((hieu van) OR (thien van)) cau tu ((ban thanh) OR (va hanh)) ki su tien.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu thanh ky nang x ho. ((hieu van) OR (thien van)) cau tu ((ban thanh) or (va hanh)) ki su tien".
• Adding a wildcard symbol may retrieve word variants: vu thanh ky nang x ho. ((hieu van) OR (thien van)) cau tu ((ban thanh) or (va hanh)) ki su tien*.