Show unused hostname(s) between a hostname and its base domain

Hi, In Advance mode, could we have the listing of all sub-level domains to assist a more efficient way to block domains? Currently there are only top-level domain (e.g. google.com) and the lowest-level domain (e.g. c.ad.google.com) listed. So if we want to block any sub-level domain in between (e.g. ad.google.com), we have to do that manually.

Thank you.