Use Remove from Selection to remove the new selection from the currently selected objects.
With several objects selected, in the toolbar click Remove from Selection
. Click one of the selection tools and select objects within that selection. The objects you selected are removed from the selection.
Choose Edit > Select Mode > Remove from Selection.
Place several objects on the canvas.
Use Box Select (or another selection tool) to select some of these objects.
Click Remove From Selection
.
Using Box Select , select some of the objects within your selection.
The new selection is removed from your original selection.