Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hieu van » hieu va, thien van, lieu va
cau phuc » cau truc, chau phu, huu phuc
su sach » so sach, vu sach
van cau » van dau, van hau, van chat
phuc va » phuc vu, thuc va, chuc va
va hang » van hang, va nang, va lang
hang ca » hang va, nang cao, hang tai
cua tre » cua te, cuu tre, cua triet
ca cua » co 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: ((su sach) or (toc sach)) ky nang x hoi. hieu van cau phuc va hang ca cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (toc sach)) ky nang x hoi. hieu van cau phuc va hang ca cua tre.
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (toc sach)) ky nang x hoi. hieu van cau phuc va hang ca cua tre*.