Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hieu van » thien van, lieu va, hieu ve
ban hanh » ban hang
ky dang » ky nang, ky danh
dang xa » dang xay, lang xa, dang ha
hieu va » lieu va, hieu qua
xuc ban » duc ban, cuc ban, quoc ban
cua tre » cua te, cuu tre, cua triet
vi cua » vai cua, di cua

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 (toc sach)) ky dang xa hoi. ((hieu van) or (hieu va)) cam xuc ban hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) ky dang xa hoi. ((hieu van) OR (hieu va)) cam xuc ban hanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (toc sach)) ky dang xa hoi. ((hieu van) or (hieu va)) cam xuc ban hanh vi cua tre*.