Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
quan van » luan van, quan va, quan luan
sach ky » sac ky, sach y, sach ty
hieu ha » hieu hoa, hieu va, hieu ca
cuu tre » cua tre, cau tren, cau treo
qua va » quan va, qua van, vua va
vi cuu » vi luu, vinh cuu
x hoi » xa hoi, x ho, 5 hoi
o hoi » co hoi, o hoc, o hai

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ky nang ((x hoi) or (o hoi)). hieu ha nam ((qua va) or (quan van)) hanh vi cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky nang ((x hoi) OR (o hoi)). hieu ha nam ((qua va) OR (quan van)) hanh vi cuu tre.
• Adding a wildcard symbol may retrieve word variants: thu sach ky nang ((x hoi) or (o hoi)). hieu ha nam ((qua va) or (quan van)) hanh vi cuu tre*.