Sometimes you cannot launch programs from the search, it is not because Windows 10 broke down. It is because Windows 10 finds out applications from the search but it is unable to launch them. It is a small bug that Windows 10 comes up with. In case you can find the app but you can not launch it then you need to fix it by enabling the background apps and performing some checks.
Before trying any fix, you need to fist check different details.
Check the file you are trying to run from the search is an app or a shortcut. In case it is a shortcut, you need to find out the actual app and see whether it is installed or not.
Also, make sure that the app is not corrupt and look for the app in the list of apps and try running it from the File Explorer before.
To make sure that the problem exists, try running any built-in app from the search such as Notepad.
Disable any kind of application that is modifying the Graphical User Interface of Windows 10 along with the taskbar. If you have all the settings in order then you must follow the procedure to fix the programs that are not launching from the search.
Fixing Programs that are not Launching from the Search
Open Settings and go to Privacy Settings. Scroll the list of tabs on the left and choose the background apps tab. Find ‘Let apps run in the background’ option and turn on the switch. There is no need to enable the apps to run in the background.
Turning the background apps on will let the search work and makes it possible to launch apps from the Search. While using Cortana, you need to sign out of Cortana by clicking the Cortana on the taskbar and click on the menu button on the top left. Click sign out from the panel under name and email.
It is good to restart the system and check for the changes you previously made. It will make the applications launch from Windows Search. Now you can sign back to Cortana again.