[Joe]

This is not currently supported. These groups (sometimes we refer to them as "families") are intended to be simplistic and geared towards basic use cases.

If you're craving more customization, you might want to consider changing your grouping preferences. Go to Manage > Preferences > Navigation View and you'll see the settings for "Similar Topic Grouping". By default it's set to group topics "By Simple Grouping".

If you change this to "By Category", category headings will be used instead. This will cause topics to be grouped by category. You can then fully customize what categories you use (including adding, hiding, and renaming) by going to Manage > Categories.

Another option would be to forego the headings altogether and use the topic hierarchy alone to manage and organize things. To do this, go to the nav pane options menu (the tools icon next to the magnifying glass icon), and uncheck "Group Similar Kinds of Topics". With this approach, you'd create whatever containers you like to organize things. It's a bit more advanced and free-form, but it does give you some more control.

Hopefully this helps.