Hello,
We don’t see reasons of this issue from the theme side. But you are using a lot of third-party plugin and WPML that slows down the site. Check the WPML plugin docs if they have any suggestions how to speed up their plugins and also disable all the plugins that you don’t really use, every additional plugin slows down the site a little bit.
In addition, I see a number of errors in your errors log related to WooCommerce http://prntscr.com/snjcb1 Make sure that it was fixed.
Regards