Perhaps you should try some spelling variations:
nham thuc » nhan thuc, nam thuc, nham thu
toc sach » hoc sach, thuoc sach, nuoc sach
doc sach » hoc sach, nuoc sach, dac sac
hieu van » hieu va, thien van, lieu va
van nham » van nam, van nhan, van tham
su sach » so sach, vu sach
nang xa » nang x, lang xa, nang ma
thuc va » thuc vat, thuc dan, thuc day
va hanh » van hanh, va thanh, va danh
cua tre » cua te, cuu tre, cua triet
vi cua » vai cua, di cua

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) OR (((toc sach) OR (doc sach)))) ky nang xa hoi. hieu van nham thuc va hanh vi cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) or (((toc sach) OR (doc sach)))) ky nang xa hoi. hieu van nham thuc va hanh vi cua tre~".
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (((toc sach) OR (doc sach)))) ky nang xa hoi. hieu van nham thuc va hanh vi cua tre*.