In Principal Menu i want to add sub-itens to sub-itens, like this:
But in the page does not appear:
Sorry for the inconvenience.
However, this theme is not supporting 3rd level menu by default based on the theme UX & UI. In this issue, you need to customize the theme to get support 3d level menu.
Moreover, we have listed this in our theme update list. We will try to add this feature in our next update of the theme.
Thanks for your understanding.
ThemeLooks Support Team