Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hanh vai » hanh vi, hanh va, hanh tai
dang van » hoang van, hang va
tu sach » thu sach, su sach, te sach
vai cua » dai cua, hai cua, lai cua
thuc va » thuc vat, thuc dan, thuc day
hieu ve » hieu va, hieu van
ve cham » va cham, ve chat, vu cham
van hoi » van hoa, van hoc, van hoe
ky dang » ky nang, ky danh
cua tre » cua te, cuu tre, cua triet

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu sach) or (toc sach)) ky dang van hoi. hieu ve cham ((tuc xa) or (thuc va)) hanh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (toc sach)) ky dang van hoi. hieu ve cham ((tuc xa) OR (thuc va)) hanh vai cua tre.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (toc sach)) ky dang van hoi. hieu ve cham ((tuc xa) or (thuc va)) hanh vai cua tre*.