Perhaps you should try some spelling variations:
hieu hien » bieu hien, dieu hien, chieu chien
hien cac » thien cac, vien cac, hieu cac
va triet » va thiet, va trien, ve triet
sach ky » sac ky, sach y, sach ty
luc van » luoc van, duc van, luc va
luu van » cuu van, luan van, luu hanh
ky dang » ky nang, ky danh
danh tu » anh tu, doanh thu
te sach » toc sach
va hoi » va hoc, va hoa

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 dang ((va hoi) OR (xa hoi)). hieu hien cac ((luc van) OR (luu van)) danh tu va triet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky dang ((va hoi) OR (xa hoi)). hieu hien cac ((luc van) or (luu van)) danh tu va triet~".
• Adding a wildcard symbol may retrieve word variants: te sach ky dang ((va hoi) OR (xa hoi)). hieu hien cac ((luc van) or (luu van)) danh tu va triet*.