Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
va thanh » ban thanh, va tinh, le thanh
sach ky » sac ky, sach y, sach ty
tu sach » thu sach, su sach, te sach
nang ma » tang ma, sang ma, nang cao
va cao » va cac, va co, va dao
va cam » va cham, va cac, va cai
ma hoi » mai hoi, xa hoi, ma hoa

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