Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hieu van » hieu va, thien van, lieu va
duoc van » duoc va, duc van, duoc ban
va triet » va thiet, va trien, ve triet
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
da duoc » tao duoc, hoa duoc
hanh va » hang va
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: toc sach ky nang xa hoi. hieu van da duoc van ((hanh va) OR (hanh vi)) va triet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ky nang xa hoi. hieu van da duoc van ((hanh va) OR (hanh vi)) va triet".
• Adding a wildcard symbol may retrieve word variants: toc sach ky nang xa hoi. hieu van da duoc van ((hanh va) OR (hanh vi)) va triet*.