@weakchin179
Go into settings, make sure Advance Settings is checked
Scroll down to Display, make sure Display clips list is checked
Now go to the card you want to delete clips from, uncheck clips that you want to delete
After you have done that, click the main page of the card (the one with the card picture)
Right click on the trash can, select Delete disabled clips, confirm deletion by clicking Yes only once, clips will be deleted.
Hope that helps......