Perhaps you should try some spelling variations:
vu sach » vu bach, vu khach
va tinh » may tinh
va hanh » van hanh, va thanh, va danh
hieu va » lieu va, hieu qua
cac toc » cac toi, cac nuoc, cac thoi
su sach » so sach
cua tre » cua te, cuu tre, cua triet
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: ((vu sach) or (su sach)) ky nang x hoi. hieu va cac toc ((va hanh) or (va tinh)) vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((vu sach) OR (su sach)) ky nang x hoi. hieu va cac toc ((va hanh) OR (va tinh)) vi cua tre.
• Adding a wildcard symbol may retrieve word variants: ((vu sach) or (su sach)) ky nang x hoi. hieu va cac toc ((va hanh) or (va tinh)) vi cua tre*.