You can import additional font icons like this:
1. Go to http://fontello.com
2. Click on this icon from middle page then press import
3. Go to main zip file that you have downloaded from Themeforest in this path : /MainFiles/Assets/Fontello
4. Import/upload config.json
5. Icons from KLEO will appear and you can select additional icons
6. When you are done just press Download Webfont button
7. Extract the pack in kleo-child/assets
The assets folder from KLEO child theme should look like this :
The config.json file should be in root assets folder
IMPORTANT : If you don't see the icons in the menu area from example you will have to re-save theme options.
IMPORTANT 2 : If you have any cache plugin you will have to purge/empty all caches modules !
Note : Child theme needs to be installed and activated