As you can see in the Units list, ThrdDemo uses two units from the same folder, SortThds and ThSort. Click on the SortThds (on the unit name, not into the checkbox). GpProfile will fill the Classes and Procedures lists with names of classes and procedures declared in unit SortThds.
Now click on class TBubbleSort in the Classes list. GpProfile will update Procedures list to contain only the methods from the TBubbleSort class. If you now click on the Sort procedure (the only one), GpProfile will load file SortThds.pas into the bottom window and position it at the beginning of the Sort procedure.