Why coulndn't find the HR2VP App in ConnectIQ App Store

Probably because it is either not compatible with you device, or it is not available in your country. Recently, all EU countries are restricted, and developers have to obtain a special registration of offering their apps in the EU. 

You can see the app in the web store, though: https://apps.garmin.com/apps/ab94e897-c1a0-4d5c-9688-89ecfb11126a