Hover over an entity and take a quick blueprint of everything in its selection area with CONTROL+Q.

Can someone explain what a "selection area" is and how to make a Ctrl-Q blueprint that includes more than one entity? I did it once by accident and I can't replicate it.

The selection are is the yellow box that shows up when you hover over an entity, To select things in an area use CTRL-Q on empty ground until a blank blueprint shows up in your hand. then you can click/drag like a regular blueprint