Perhaps you should try some spelling variations:
thanh vi » hanh vi, thanh va, thanh ve
hieu van » hieu va, thien van, lieu va
dang xay » dang van, van xay
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
van lam » van nam
lang ha » long ha
cua tre » cua te, cuu tre, cua triet
lao va » tao va, cao va, bao va
vi cua » vai cua, di cua
lo va » lo van, ly va, le va

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

• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky ((lang ha) OR (dang xay)) hoi. hieu van lam ((lo va) OR (lao va)) thanh vi cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky ((lang ha) or (dang xay)) hoi. hieu van lam ((lo va) OR (lao va)) thanh vi cua tre~".
• Adding a wildcard symbol may retrieve word variants: su sach ky ((lang ha) or (dang xay)) hoi. hieu van lam ((lo va) OR (lao va)) thanh vi cua tre*.