我正在尝试使用这个模型过滤博客文章：

class Post(models.Model):
    is_podcast = models.BooleanField(default=False)
    category = models.ManyToManyField(Category)
    title = models.CharField(max_length=500)
    slug = models.SlugField(allow_unicode=True , unique=True , null=True , blank=True)
    body = RichTextUploadingField()
    likes_count = models.IntegerField(default=0 , help_text="amount of likes")
    vip_members_only = models.BooleanField(default=False)

    def __str__(self):
        return self.title

我使用这个视图来过滤帖子：

def Index_view(request , slug=None):
    posts = Post.objects.filter()
    kind = request.GET.get('type')
    order = request.GET.get('order')
    author = request.GET.get('author')
    search = request.GET.get('search')

    if slug:
        cat = get_object_or_404(Category , slug=slug)
        posts.filter(category = cat)

    if search != '' and search is not None:
        posts.filter(Q(title__icontains = search))

    if kind != '' and kind is not None:
        if kind == 'podcast':
            posts.filter(is_podcast=True)
        if kind == 'all':
            pass
        if kind == 'post':
            posts.filter(is_podcast=False)  

    con = {'posts' : posts}
    return render(request , 'Weblog/posts.html' , con)

下面是urls.py：

path('posts/', Index_view),
re_path(r'^posts/(?P<slug>[\w-]+)/$', Index_view),

当我使用这个URL（http://127.0.0.1:8000/blog/posts/some-slug/?search=test）时，我收到了所有的帖子，过滤不起作用。有什么问题吗？