Perhaps you should try some spelling variations:
chat triet » chet triet, phat trien, chat thien
kho tang » cao tang
hanh lam » thanh lap, hanh kem, hanh va
lam chat » luan chat, cao chat, ly chat
tu sach » thu sach, su sach, te sach
ky tang » ky nang, ky dang, ky trong
van bac » van bao, van hac, dan bac
va hanh » van hanh, va thanh, va danh

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