Hello,
If elements were create using VC, you can use Responsive Options http://prntscr.com/j6b3hl
also, code like,
.class-of-element {
display: none;
}
can be added in Theme Options > Styling > Custom css > Custom css for mobile or desctop. Use devtools in chrome browser to find required class.
Let us know if you need any further assistance.
Regards