Hi Yamabii
Your minidump files indicate two drivers as the cause of your system crashes.
A virtual driver associated to Avast Anti-Virus is the main cause of your system crashes.
Temporarily uninstall Avast using the Avast Removal Tool they provide on their website.
Wait to see if your system is stable.
You can then install the latest version of Avast, if you wish to continue using Avast.
Also, the device driver on your Nvidia graphics was listed in one of the minidump files.
I uninstalling Avast does not stabilize your system, completely remove the current Nvidia device driver using the widely available free DDU utility, then restart your PC and go to the support page for your PC on the manufacturer's website to download and install their recommended version of the Nvidia device driver.