If newly installed applications are not showing up in Spotlight, then try restarting Spotlight indexing:

sudo mdutil -a -i off
sudo mdutil -a -i on

If that doesn’t work, then try rebooting the service as well:

sudo mdutil -a -i off
sudo launchctl unload -w /System/Library/LaunchDaemons/com.apple.metadata.mds.plist
sudo launchctl load -w /System/Library/LaunchDaemons/com.apple.metadata.mds.plist
sudo mdutil -a -i on

Source: https://apple.stackexchange.com/a/142523