On the Design Study Bar, expand the Material branch. Right click on one of the parts called M-Chip, and select Create New Group.
On the Add to Group dialog, enter "medium chips" as the group name. Leave the Type as Geometric.
Click OK.
Right click on the other M-CHIP part from the list, and select Add to Existing Group.
Select the medium chips group.
Click OK.
If the model parts are all named "Part*", it will be very difficult to select them from the Design Study bar. To add the medium chips to the group, select both chips:
Right click off the model, and click Group > Create group. On the Add to group dialog, make sure Create new group is selected, and enter medium-chips, and OK. To finish, right click off the model, and click Deselect all.