Windows 10 search is not working properly

I have various issues with windows search. This is a week old clean install of windows 10. The related service is running OK.

1. If I type paint then there is no result. (worked on win7/8). I have to type mspaint to get into paint.
2. If I typed notep into search on win7/8 it gave me the notepad app "real-time". In windows 10 there is no result unless I type exactly(!) notepad into the search bar. This applies for EVERYTHING. Typing calcul won't result in seeing calculator.
3. Typing 'word' returns no result. I had to create a shortcut and click on it to open MS Word. This is very inconvenient.
4. It can't find any software installed.

The best thing in previous windows versions was the search. Just enter start menu or hit winbutton+q and start typing. But now it doesn't work. I have rebuilt index in Control Panel -> Indexing Options -> Advanced several times, but didn't help. Checked the service, it seems to be OK. Do you have any suggestion to make windows search usable again?

Solution 1:

Solution found!

Run the below in PowerShell:

Get-AppXPackage -Name Microsoft.Windows.Cortana | 
Foreach {Add-AppxPackage -DisableDevelopmentMode -Register 
"$($_.InstallLocation)\AppXManifest.xml"}

Solves the issue right away, without any restart.