Perhaps you should try some spelling variations:
su triet » su viet, ve triet
hanh cat » hanh cac, hanh luat, nhanh cay
so sach » so sanh, bo sach, co sach
sach ky » sac ky, sach y, sach ty
va hanh » van hanh, va thanh, va danh
cam luc » cam xuc, cau luc
su tien » su kien, su hien, tu tieng
sang ma » tang ma, nang ma, sang tao
hieu va » hieu qua
ky sang » ky nang, ky dang, ky tang
luc va » duc va, tuc va, loc va
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: so sach ky sang ma hoi. ((hieu va) OR (lieu va)) cam luc va hanh cat ((su triet) or (su tien))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ky sang ma hoi. ((hieu va) OR (lieu va)) cam luc va hanh cat ((su triet) OR (su tien)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach ky sang ma hoi. ((hieu va) OR (lieu va)) cam luc va hanh cat ((su triet) or (su tien))".
• Adding a wildcard symbol may retrieve word variants: so sach ky sang ma hoi. ((hieu va) OR (lieu va)) cam luc va hanh cat ((su triet) or (su tien))*.