How to include more files in Blank Element in SharePoint 2013 project in visual studio?

I have a sharepoint 2013 blank solution project in visual studio. I made a "Empty Element" and it shows an item, which containsElements.xml. What I am trying to do is add a custom xml file as a sibling to Elements.xml. And also, so that if I open a feature in Design mode, and see the list ofitems in the solution, then expand the element object I created. I expect to see bothElements.xml and my custom xml file. But the problem is that I only see the Elements.xml. Somehow my custom file is not being included there.

To create the custom xml file, I just right clicked the element object, and clicked Add from existing file, and then I added the xml file. But its not being recognized by the Design mode.

I tried a hack, where I created another empty element, and renamed its elements.xml and put it as a sibling to my first elements.xml, and that was recognized, but I don't think this is the right way to do it.

I want to add a file here where the red arrow is.

Does anyone know?

Thanks