Hi,
1. Right click the Avast icon in the system tray and choose On-Access Protection;
2. Click the details...>> button (only if you have not done so before) to show all the details for the On-Access Protection providers;
3. For the provider(s) that the messages are coming from select Customize;
4. Select the advanced tab;
5. Uncheck the box that says 'Show detailed info on performed action';
6. OK your way out.
Note: Only some residents have this option you won't find this option in everyone. You may also want to find just the one resident that keeps displaying all the alerts (probably Standard Shield and / or Webshield) and allow the others to show the information, but this depends on your preferences.
Hope this helps.
Mike