Perhaps you should try some spelling variations:
van thanh » van tuan
ban thanh » ban hanh, ban hang
te sach » toc sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va, hieu van
cu tren » tu tren, dua tren
ve cac » va cac, vien cac
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 nang xa hoi. hieu ve cac du ((van thanh) OR (ban thanh)) vi cu tren~.
• Adding a wildcard symbol may retrieve word variants: te sach ky nang xa hoi. hieu ve cac du ((van thanh) or (ban thanh)) vi cu tren*.