Mixed content issue on wordpress site

Hi,
my site was build with a theme purchased from themeforest. and today i have enabled ssl for my site. everything is fine except all the images are serving from http rather then https. all other js,css etc is serving through https.

i am actually little noob here and cant figure out from where to change those images links to https from http. i have checked items which are serving from http also have https version available.

i went to edit pages from wordpress admin panel but couldnt find any link in the “text” tab.i think its because i have visual composer installed and all my pages are serving through css.

what should i do to fix those images to avoid mixed content?

thanks in advance for reading my post