Hello,
You may add a custom class for every rows, columns of which you want to change on mobile, http://prntscr.com/i25pks et-mobile-columns
and add this code in Theme Options > Custom css > Global Custom css:
@media only screen and (max-width: 768px) {
.et-mobile-columns .vc_col-sm-4 {
width: 33.33%;
float: left;
}
.et-mobile-columns .vc_col-sm-3,
.et-mobile-columns .vc_col-sm-2,
.et-mobile-columns .vc_col-sm-6 {
width: 50%;
float: left;
}
}
OR
use responsive options of columns http://prntscr.com/i25r0u
https://wpbakery.com/video-academy/responsive-column-control-width-offset-param-usage-explained/
Regards