Perhaps you should try some spelling variations:
ban hanh » ban hang
van hanh » van thanh, van anh, van ban
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
hieu va » lieu va, hieu qua
ca viet » va viet, co viet, hoa viet
va cam » va cham, va cac, va cao
vai ca » vai cac, vai cua, bai ca
5 hoi » o hoi

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ky nang ((5 hoi) or (x ho)). hieu va cam xuc ((ban hanh) or (van hanh)) vai ca viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky nang ((5 hoi) OR (x ho)). hieu va cam xuc ((ban hanh) OR (van hanh)) vai ca viet.
• Adding a wildcard symbol may retrieve word variants: su sach ky nang ((5 hoi) or (x ho)). hieu va cam xuc ((ban hanh) or (van hanh)) vai ca viet*.