Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
hieu van » hieu va, thien van, lieu va
cua viet » ca viet, hoa viet, cua vat
te sach » toc sach
van cau » van dau, van hau, van chat
cau duc » cao duc, cau luc, chu duc
va hanh » van hanh, va thanh, va danh
hanh di » hanh vi, hanh de, hang di
cua tre » cua te, cuu tre, cua triet
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: ((te sach) or (thu sach)) ky nang x hoi. hieu van cau duc va hanh di ((cua tre) or (cua viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (thu sach)) ky nang x hoi. hieu van cau duc va hanh di ((cua tre) OR (cua viet)).
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (thu sach)) ky nang x hoi. hieu van cau duc va hanh di ((cua tre) or (cua viet))*.