Perhaps you should try some spelling variations:
hanh vai » hanh va, hanh tai, hanh van
su triet » su viet, su tien, ve triet
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
ve bac » ve bao, ve cac, ve ban
bo van » vo van, so van, do van
x hoi » o hoi, x ho, 5 hoi

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