Perhaps you should try some spelling variations:
qua nhan » cua nhan, qua nhat, qua phan
hanh doi » thanh doi, hanh noi, hang doi
su sach » so sach, vu sach
mai hoi » mai khoi, dai hoi, lai hoi
doi cua » dai cua, hoi cua
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, v nang
ma hoi » xa hoi, ma hoa, me hoi
luc va » tuc va, loc va

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

• If you are trying to use Boolean operators, they must be ALL CAPS: su sach y nang ((ma hoi) OR (mai hoi)). hieu qua nhan ((luc va) OR (duc va)) hanh doi cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach y nang ((ma hoi) OR (mai hoi)). hieu qua nhan ((luc va) or (duc va)) hanh doi cua tre~".
• Adding a wildcard symbol may retrieve word variants: su sach y nang ((ma hoi) OR (mai hoi)). hieu qua nhan ((luc va) or (duc va)) hanh doi cua tre*.