Perhaps you should try some spelling variations:
vua triet » cua triet, va triet, va trien
hoc sach » hoc sinh, hoc cac, hoc anh
hieu van » hieu va, thien van, lieu va
duoc van » duoc va, duc van, duoc dan
duoc ban » duc ban, quoc ban, buoc ban
sach ky » sac ky, sach y, sach ty
nang xa » lang xa, nang ma, mang xa
hanh va » hang va, hanh vi
van da » van dao, van dau, van dan

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc sach ky ((nang xa) or (nang x)) hoi. hieu van da ((duoc van) OR (duoc ban)) hanh va vua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc sach ky ((nang xa) OR (nang x)) hoi. hieu van da ((duoc van) OR (duoc ban)) hanh va vua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc sach ky ((nang xa) or (nang x)) hoi. hieu van da ((duoc van) OR (duoc ban)) hanh va vua triet".
• Adding a wildcard symbol may retrieve word variants: hoc sach ky ((nang xa) or (nang x)) hoi. hieu van da ((duoc van) OR (duoc ban)) hanh va vua triet*.