Knowledge Base Articles - Custom Search & Add New From Case Form

Hi, 

I just want to know if there is a possibility of adding custom fields to KB Articles and add them to Search Picklist. For example for Product and Version, I have already added them to Article Entity, but can I allow the Search based on these, as the option for searching KB Article is limited to Subject, Keyword and few more.

ALso can I add directly a KB Article from the Case form, as from there you can only attach one to it, but you cannot create a new one directly from Case Screen.

Thanks