In his case I think he’s smart restricting his site to Facebook marketing because that alone is a massive topic and it probably takes all of his time to remain an expert with Facebook marketing, updating his courses and blogging about it in such a high quality manner.
家用摄像头网上专卖店满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满意意满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满满意意了我是我是我是我是我是我是我是非常满意！。