Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
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
ban so » ban do, ban co, ban su
ban bo » can bo, ban do, ban co
vi su » va su, ve su, ki su

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. hieu ve ((ban so) or (ban bo)) van hanh vi su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang x ho. hieu ve ((ban so) OR (ban bo)) van hanh vi su triet.
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang x ho. hieu ve ((ban so) or (ban bo)) van hanh vi su triet*.