Perhaps you should try some spelling variations:
doc sach » hoc sach, toc sach, nuoc sach
sach tay » xach tay, sach hay, sach nay
tay lang » tai lang, tay tang, tay quang
hieu van » hieu va, thien van, lieu va
lam duoc » nam duoc, luat duoc, lam thuoc
chua tre » chua tri, cua tre, chua trieu
lang xa » lang ha, dang xay, lang van
van lam » van nam
va hang » van hang, va lang, va hanh
va nang » van nang, da nang, cam nang
va chua » vua chua, ca chua, va chu

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc sach tay lang xa hoi. hieu van lam duoc ((va hang) or (va nang)) va chua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc sach tay lang xa hoi. hieu van lam duoc ((va hang) OR (va nang)) va chua tre.
• Adding a wildcard symbol may retrieve word variants: doc sach tay lang xa hoi. hieu van lam duoc ((va hang) or (va nang)) va chua tre*.