Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
su sach » so sach, vu sach
va hanh » van hanh, va thanh, va danh
hieu ve » hieu va, hieu van
lang ha » long ha
lang xa » dang xay, lang van
cua tre » cua te, cuu tre, cua triet
ve cam » ve cham, ve cac, va cam
xuc va » duc va, tuc va, luc va
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: ((su sach) or (toc sach)) ky ((lang xa) or (lang ha)) hoi. hieu ve cam xuc va hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (toc sach)) ky ((lang xa) OR (lang ha)) hoi. hieu ve cam xuc va hanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (toc sach)) ky ((lang xa) or (lang ha)) hoi. hieu ve cam xuc va hanh vi cua tre*.