Perhaps you should try some spelling variations:
chat triet » chet triet, phat trien, chat thien
nang ma » tang ma, sang ma, nang cao
nang xa » nang x, lang xa, mang xa
sach ky » sac ky, sach y, sach ty
van bac » van bao, van hac, dan bac
va hanh » van hanh, va thanh, va danh
hanh va » hang va, hanh vi
va chat » van chat, va phat, cao chat
tu sach » thu sach, su sach, te sach
xuc va » duc va, tuc va, luc va

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