Perhaps you should try some spelling variations:
van thanh » ban thanh, van tuan
cua triet » cua viet, su triet, va triet
sach ty » sach tu, sach thu, xach tay
dang xa » dang xay, lang xa, dang ha
qua cac » cua cac
cac luc » cau luc, coc luc, cac nuoc
va hanh » van hanh, va thanh, va danh
vi cua » vai cua, di cua

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 ty) OR (sach y)) dang xa hoi. hieu qua cac luc ((va hanh) OR (van thanh)) vi cua triet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach ty) OR (sach y)) dang xa hoi. hieu qua cac luc ((va hanh) or (van thanh)) vi cua triet~".
• Adding a wildcard symbol may retrieve word variants: su ((sach ty) OR (sach y)) dang xa hoi. hieu qua cac luc ((va hanh) or (van thanh)) vi cua triet*.