如何过滤各个字段

Question

我在视图中有一段代码，我打算过滤名为OrderItem的数据库模型中的所有各个字段。

以下是代码：

def search_form(request):

    if 'q' in request.GET and request.GET['q']:
        x = request.GET['q']
        q = x.title()

        print q

        x = request.GET['certification_type']
        print x

        items = OrderItem.objects.filter(Q(order_type__iexact=x and order_type__iexact=q) | Q(certification_type__iexact=x and certification_type__iexact=q) | Q(item__iexact=x and item__iexact=q)
         | Q(certification_no__iexact=x and certification_no__iexact=q) | Q(client__user__email__iexact=x and client__user__email__iexact=q) | Q(client__phone_number__iexact=x and client__phone_number__iexact=q)
         | Q(created_on__icontains=x and created_on__icontains=q))


        for x in items:
            for q in items:
                print items 



        return render(request, 'i/search_results.html', {'items':items, 'query':q})
    else:
        return render(request, 'i/search_form.html', {'error':True})

但如果我尝试在certification_type下找到项目，我会在控制台上找到空列表[]。我不知道缺少什么