Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
van thanh » van tuan
te sach » toc sach
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
lang ha » long ha
lang xa » dang xay, lang van
cu tren » tu tren, dua tren
ve cac » va cac, vien cac
cac tu » cac thu, cach tu, cac du
vi cu » vi su, vi xu, vi du

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: te sach ky ((lang xa) OR (lang ha)) hoi. hieu ve cac tu ((van thanh) OR (ban thanh)) vi cu tren~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky ((lang xa) OR (lang ha)) hoi. hieu ve cac tu ((van thanh) or (ban thanh)) vi cu tren~".
• Adding a wildcard symbol may retrieve word variants: te sach ky ((lang xa) OR (lang ha)) hoi. hieu ve cac tu ((van thanh) or (ban thanh)) vi cu tren*.