syntax error: select * from sanpham where (idDM =  or idDM in (select idDM from danhmuc where cap1 = ) or idDM in (select idDM from danhmuc where dmCha = ) or idDM in (select idDM from danhmuc where dmCha in (select idDM from danhmuc where cap1 = ))) or (idDM2 =  or idDM2 in (select idDM from danhmuc where cap1 = ) or idDM2 in (select idDM from danhmuc where dmCha = ) or idDM2 in (select idDM from danhmuc where dmCha in (select idDM from danhmuc where cap1 = ))) order by vitri, idSP DESC