Rebuild Windows Search Index:
Press Win + R to open Run menu and type:
control /name Microsoft.IndexingOptions
Click Advanced.
Under Troubleshooting, click Rebuild.
If the above doesn't help then open PowerShell as Admin and copy-paste the following:
Get-AppxPackage MicrosoftWindows.Client.CBS | Reset-AppxPackage
Reboot.
Sometimes the user profile is corrupted. Create a new user profile to check.