I'm not sure I fully understood the question but I'll try to answer.
The widget will show top X results matching the query and filters. If you want to see only specific applications or hide specific applications I recommend adding them as filter to specific widgets or the entire report, depends on if you want to apply it on the entire view.
1. If you want to filter out some application, I suggest using right click and filtering out all the widgets you don't want to see, then copy the query line that was created by filtering out and add it as a custom filter to the widget/view, this will filter them out permanently.
2. If you want to filter in only specific applications you can either go the other way (filter in) or create a user category that includes all the application you want to see and use that category as a filter (which would be the easier way IMO).
Kind regards, Amir Senn