Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
truc van » truc va, thuc van, truc ban
van hanh » van thanh, ban hanh, van anh
vu nang » vuc nang, va nang, vu dang
da nang » cam nang, kha nang, cao nang
kem cua » em cua, keo cua, diem cua
cua tre » cua te, cuu tre, cua triet
v nang » va nang, van nang, voi nang
va cau » van cau, va cac, va dau

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 ((((v nang) or (vu nang))) or (da nang)) xa hoi. lieu va cau truc van hanh kem cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ((((v nang) OR (vu nang))) OR (da nang)) xa hoi. lieu va cau truc van hanh kem cua tre.
• Adding a wildcard symbol may retrieve word variants: toc sach ((((v nang) or (vu nang))) or (da nang)) xa hoi. lieu va cau truc van hanh kem cua tre*.