The Colour Categories window starts off like the Find window but adds colour options.

 

Example

With a word list I started by specifying what I wanted to find, words ending -ED.

After pressing OK I got this window:

 

When I chose the colour yellow and pressed Add a search, I got this:

 

Now pressing Find all I got this:

 

 

The word  list shows the hits with the Set column coloured.

To group the words ending in -ED, I need to choose the Alphabetical view and sort on the Set column.