Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
thanh vai » thanh hai, thanh van, thanh tai
cua viet » ca viet, hoa viet, cua vat
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
duc ban » duc tan, duc van, dua ban
vai cua » dai cua, hai cua, lai cua
va cam » va cham, va cac, va cai
va cao » va cac, va co, va dao
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)). lieu ((va cam) or (va cao)) duc ban thanh vai cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang ((x hoi) OR (xa hoi)). lieu ((va cam) OR (va cao)) duc ban thanh vai cua viet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang ((x hoi) OR (xa hoi)). lieu ((va cam) or (va cao)) duc ban thanh vai cua viet*".