Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
hanh lai » hanh lam, hanh tai, thanh lap
tu sach » thu sach, te sach, tu cach
hieu ve » hieu va, hieu van
lai cua » dai cua, hai cua, lai chau
su sach » so sach, vu sach
duc van » duc va, duc tan, duc manh
ve pham » vi pham, v pham, ve phan
co hoi » co hoc, co loi
cua te » cua tu
o hoi » o hoc, o hai, o hoa

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) or (su sach)) ky nang ((o hoi) OR (co hoi)). hieu ve pham duc van hanh lai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (su sach)) ky nang ((o hoi) OR (co hoi)). hieu ve pham duc van hanh lai cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (su sach)) ky nang ((o hoi) OR (co hoi)). hieu ve pham duc van hanh lai cua te".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (su sach)) ky nang ((o hoi) OR (co hoi)). hieu ve pham duc van hanh lai cua te*.