Perhaps you should try some spelling variations:
nham thuc » nhan thuc, nam thuc, nham thu
va thanh » gia thanh, ban thanh, va tinh
ban hanh » ban hang
toc sach » hoc sach, doc sach, thuoc sach
hieu ve » hieu va, hieu van
ve nham » ve nha, ve cham
sach ky » sac ky, sach y, sach ty
cua tre » cua te, cuu tre, cua triet
vi cua » vai cua, di cua
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: toc sach ky nang ((xa hoi) or (o hoi)). hieu ve nham thuc ((ban hanh) or (va thanh)) vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky nang ((xa hoi) OR (o hoi)). hieu ve nham thuc ((ban hanh) OR (va thanh)) vi cua tre.
• Adding a wildcard symbol may retrieve word variants: toc sach ky nang ((xa hoi) or (o hoi)). hieu ve nham thuc ((ban hanh) or (va thanh)) vi cua tre*.