Perhaps you should try some spelling variations:
chat triet » chet triet, phat trien, chat thien
thu sach » thuat sach, thuoc sach, thu hoach
van hang » van khang, van hoang, van thang
hieu van » hieu va, thien van, lieu va
va chat » van chat, va phat, cao chat
xuc van » duc van, luc van, vuc van
van bac » van ban, van bao, van hac
tu sach » su sach, te sach, tu cach
nang xa » nang x, lang xa, mang xa
nang ma » tang ma, sang ma, nang cao

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