Use Remove from Selection 
to remove the new selection from the currently selected stitches.
Remove from a Selection
-
Place an embroidery on the work area.
-
Use Box Select
(or another selection tool) to select some stitches.
-
Click Remove From Selection
.
-
Click Box Select
and select some of the stitches within your selection.
The new selection is removed from your original selection.
Shortcuts
-
Select Toolbar:
