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