Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
hanh vai » hanh vi, hanh va, hanh tai
va triet » va thiet, va trien, ve triet
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
ve ban » te ban, va ban, vu ban
ve bao » te bao, va bao
bo van » vo van, so van, do van
vai va » mai va, dai va, hai va

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

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