Perhaps you should try some spelling variations:
dan thanh » dang thanh, danh thanh, ban thanh
hieu van » hieu va, thien van, hieu ve
nam thuc » nam thuoc, am thuc, nam thu
thuc dan » thuc hanh, hoc dan, thuc vat
thanh vi » hanh vi, thanh va, thanh ve
su sach » so sach, vu sach
te sach » toc sach
nang xa » nang x, lang xa, nang ma
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 (te sach)) ky nang xa hoi. ((hieu van) OR (lieu va)) nam thuc dan thanh vi cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) or (te sach)) ky nang xa hoi. ((hieu van) OR (lieu va)) nam thuc dan thanh vi cua tre~".
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (te sach)) ky nang xa hoi. ((hieu van) OR (lieu va)) nam thuc dan thanh vi cua tre*.