Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
van hanh » van thanh, ban hanh, van ban
hieu van » hieu va, thien van, lieu va
vai cua » dai cua, hai cua, lai cua
van anh » van thanh, tuan anh, van minh
tu sach » thu sach, su sach, te sach
cau duc » cao duc, cau luc, chu duc
sach ky » sac ky, sach y, sach ty
lang xa » lang ha, dang xay, lang van
nang xa » nang x, nang ma, mang xa
van cau » van dau, van hau, van chat

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