Mohammad Taqui Sayed

That’s not a problem, Supernova is responsive and that’s how its supposed to do in phone and tablets. I think you want to show the same design in small screens as well correct?

Yes, (I hope you are using the latest version).
Go to Appearance>supernova options>general and paste this in ‘write custom css’

.single .entry .supernova_thumb{display: none}

and that’s it.

You would have to remove couple more things from script.
open main.js file (uncompress it using jsbeautifier.org) and remove this script

jQuery(document).ready(function (e) {
    var t = window.innerHeight + "px";
    if (window.innerWidth < 980) {
        jQuery("#top_most, #nav_wrapper").css({
            height: t
        });
        jQuery("#top_most, #nav_wrapper ").css({
            overflow: "auto"
        })
    } else {
        jQuery("#top_most, #nav_wrapper").css({
            overflow: "visible"
        });
        jQuery("#top_most, #nav_wrapper").css({
            height: "auto"
        })
    }
    jQuery(".media_left").click(function () {
        jQuery("#header_navigation").animate({
            width: "toggle"
        })
    });
    jQuery(".media_left_close").click(function () {
        jQuery("#header_navigation").animate({
            width: "toggle"
        })
    });
    jQuery(".media_right").click(function () {
        jQuery("#nav_wrapper").animate({
            width: "toggle"
        })
    });
    jQuery(".media_right_close").click(function () {
        jQuery("#nav_wrapper").animate({
            width: "toggle"
        })
    })
});
jQuery(window).on("resize", function (e) {
    if (window.innerWidth < 920) {
        var t = window.innerHeight + "px";
        jQuery("#top_most, #nav_wrapper").css({
            overflow: "auto"
        });
        jQuery("#top_most, #nav_wrapper").css({
            height: t
        });
        jQuery("#title_wrapper").css({
            "margin-top": "40px"
        })
    } else {
        jQuery("#top_most, #nav_wrapper").css({
            overflow: "visible"
        });
        jQuery("#top_most, #nav_wrapper").css({
            height: "auto"
        });
        jQuery("#title_wrapper").css({
            "margin-top": "10px"
        })
    }
})

Thanks, the latest version is approved however the theme admin is taking too long to make it live, probably he is not available, so I think it should be available by Monday but I m not sure. If you are currently running this theme I know it would affect your mobile visitor because the navigation goes away in small screens, so you can download the latest version from here http://wordpress.org/themes/supernova/developers/
‘current version’ 1.4.1

Thanks

Here you go.
.flexslider .slides img {width: 100%;height: 300px;}