Perhaps you should try some spelling variations:
duc ngan » duc ngon, duc nhan, luc ngan
hang lai » hang tai, hang hai, hang loi
tu sach » thu sach, su sach, te sach
hieu ve » hieu va, hieu van
cac duc » cac du, cao duc, cac dac
lai cua » dai cua, hai cua, lai chau
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, v nang
co hoi » co hoc, co loi
ve cac » va cac, vien cac
x hoi » xa hoi, o hoi, x ho

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 y nang ((x hoi) or (co hoi)). hieu ve cac duc ngan hang lai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y nang ((x hoi) OR (co hoi)). hieu ve cac duc ngan hang lai cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach y nang ((x hoi) or (co hoi)). hieu ve cac duc ngan hang lai cua tre*.