Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
hanh lai » hanh lam, hanh tai, thanh lap
hieu van » hieu va, thien van, lieu va
nang xa » lang xa, nang ma, mang xa
sach tu » sach thu, cach tu, sach ty
van cac » van hac, van cau, van bac
cac duc » cac du, cao duc, cac dac
tu sach » thu sach, su sach, te sach

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach tu ((nang xa) or (nang x)) hoi. hieu van cac duc va ((hanh lai) or (thanh san)) su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach tu ((nang xa) OR (nang x)) hoi. hieu van cac duc va ((hanh lai) OR (thanh san)) su triet.
• Adding a wildcard symbol may retrieve word variants: tu sach tu ((nang xa) or (nang x)) hoi. hieu van cac duc va ((hanh lai) or (thanh san)) su triet*.