Trying to browse a simple .sqlite file created by swift app?

I followed a simple tutorial about core data ( core data tutorila ) and the app works. But i liked to browsed the core data by using the firefox extension. See this: browse core data with firefox

While following the tasks described in browse core data i don't see the expect values in taks 6:

• Expand the folder Table on the navigator panel on the left.
• Click on the data table of interest
• Select the button Browse & Search near the top of the app
• Select one of the records in your data table

I don't see the records with the names i added???

Also if i just add records (= different names nike, asics, puma) and i run the app i don't see these records only the previous "in-app" added records

How do i browse the core data??