Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
hieu van » hieu va, thien van, lieu va
hanh di » hanh vi, hanh de, hang di
sach ty » sach y, sach tu, sach thu
tu sach » thu sach, su sach, te sach
nang xa » nang x, nang ma, mang xa
lang xa » lang ha, dang xay, lang van
van cam » van nam, van lam, van cau
tuc va » thuc va, truc va, duc va
di cua » dai cua, doi cua, de cua

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 ty ((nang xa) or (lang xa)) hoi. hieu van cam ((tuc va) OR (tuc xa)) hanh di cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty ((nang xa) OR (lang xa)) hoi. hieu van cam ((tuc va) OR (tuc xa)) hanh di cua triet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ty ((nang xa) or (lang xa)) hoi. hieu van cam ((tuc va) OR (tuc xa)) hanh di cua triet*".