However if you do browse this website and click show all shows and arrange by date this is the order

As you can see, not all the posts are here in the feed. Its missing few important shows like technet radio or etc. I am not sure if this is intended functionality or not and/or there is criteria for having a post in the feed.

If this is intended functionality, I would like to know if there is any way I can get customize feeds as per my needs.