Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
van hanh » van thanh, ban hanh, van anh
lang xa » lang ha, dang xay, lang van
hieu ve » hieu va, hieu van
cua tre » cua te, cuu tre, cua triet
y lang » o lang, _ lang, tay lang
ve tam » ve tac, ve tai, va tam
tam tu » nam tu, cam tu, dam tu
tu van » tu 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: ((te sach) or (toc sach)) y lang xa hoi. hieu ve tam tu van hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) y lang xa hoi. hieu ve tam tu van hanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (toc sach)) y lang xa hoi. hieu ve tam tu van hanh vi cua tre*.