Adding Grouping to your Views can be a powerful way to show more information about the components hierarchy and give a cleaner view.
PS: For Block Diagram, please check out this article.
First access the Perspectives Menu:
Click Manage and then Groups.
A popular grouping rue that works very well in Block Diagran view is grouping by Parent All and Workspace. Lets choose that for this example:
This view gives you more insight into the top level of the components your are looking at. (make sure you have included all the parents references in the filter)