Perhaps you should try some spelling variations:
cuu thuc » cuu tac
tu sach » thu sach, su sach, tu cach
te sach » toc sach
hieu va » lieu va, hieu qua
thuc va » thuc vat, thuc dan, thuc day
va hanh » van hanh, va thanh, va danh
cua tre » cua te, cuu tre, cua triet
va cuu » va cau, va chu, va huu
vi cua » vai cua, di cua
x hoi » xa hoi, o hoi, x ho

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

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