Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
ban hanh » ban hang
van hanh » van thanh, van anh, van ban
cam duc » cam xuc, cao duc, pham duc
vai cua » dai cua, hai cua, lai cua
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
nang xa » lang xa, nang ma, mang xa
ve cam » ve cham, ve cac, va cam

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 (nang x)) hoi. hieu ve cam duc ((van hanh) OR (ban hanh)) vai cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky ((nang xa) OR (nang x)) hoi. hieu ve cam duc ((van hanh) OR (ban hanh)) vai cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky ((nang xa) or (nang x)) hoi. hieu ve cam duc ((van hanh) OR (ban hanh)) vai cua triet".
• Adding a wildcard symbol may retrieve word variants: tu sach ky ((nang xa) or (nang x)) hoi. hieu ve cam duc ((van hanh) OR (ban hanh)) vai cua triet*.