Perhaps you should try some spelling variations:
pham thuc » phap thuc, pham chuc, nham thuc
doc sach » hoc sach, toc sach, nuoc sach
hanh mai » hanh ma, hanh mau, hanh may
va triet » va thiet, va trien, ve triet
sach ky » sac ky, sach y, sach ty
ky sang » ky nang, ky dang, ky tang
sang ma » tang ma, nang ma, sang tao
hieu vi » hieu voi, hieu ve, hien vi
hieu va » lieu va, hieu qua
thuc va » thuc vat, thuc dan, thuc day
va hanh » van hanh, va thanh, va danh
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: doc sach ky sang ma hoi. ((hieu vi) or (hieu va)) pham thuc va hanh mai va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc sach ky sang ma hoi. ((hieu vi) OR (hieu va)) pham thuc va hanh mai va triet.
• Adding a wildcard symbol may retrieve word variants: doc sach ky sang ma hoi. ((hieu vi) or (hieu va)) pham thuc va hanh mai va triet*.