Perhaps you should try some spelling variations:
hanh vai » hanh vi, hanh va, hanh tai
van hanh » van thanh, ban hanh, van anh
tu sach » thu sach, su sach, te sach
cam tuc » cam xuc, cam tu, nam thuc
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
ky dang » ky nang, ky danh
vai cua » dai cua, hai cua, lai cua
ha hoi » hoa hoi, ha noi, va 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 dang ((ha hoi) OR (xa hoi)). hieu ve ((cam tuc) or (am thuc)) van hanh vai cua vat~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky dang ((ha hoi) OR (xa hoi)). hieu ve ((cam tuc) OR (am thuc)) van hanh vai cua vat.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky dang ((ha hoi) OR (xa hoi)). hieu ve ((cam tuc) or (am thuc)) van hanh vai cua vat".
• Adding a wildcard symbol may retrieve word variants: tu sach ky dang ((ha hoi) OR (xa hoi)). hieu ve ((cam tuc) or (am thuc)) van hanh vai cua vat*.