Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
dinh lam » dinh van, tinh lao
danh lai » danh sai, gianh lai, hanh lam
pham duy » pham duc
hieu van » hieu va, thien van, lieu va
van pham » san pham, van phan, van phat
mai hoi » mai khoi, dai hoi, lai hoi
ky dang » ky nang, ky danh
ky mang » ky nang, ke mang, ky tang
cua tre » cua te, cuu tre, cua triet
duy va » duy vat, duy van, day va

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 ((ky mang) or (ky dang)) mai hoi. hieu van pham duy va ((danh lai) or (dinh lam)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ((ky mang) OR (ky dang)) mai hoi. hieu van pham duy va ((danh lai) OR (dinh lam)) cua tre.
• Adding a wildcard symbol may retrieve word variants: toc sach ((ky mang) or (ky dang)) mai hoi. hieu van pham duy va ((danh lai) or (dinh lam)) cua tre*.