How can I get datas by mouse scrolling down

For web content, the term you're looking for is "infinite scroll".

In its simplest form, you use Javascript to detect when the user scrolls near to the bottom of your page, and then make an AJAX call to load more content.

For example, using jQuery:

$(window).on("scroll", function(){
    var $w = $(window);
    var $d = $(document);
    var padding = 50; // Load more if we're within 50 pixels of the bottom

    if ($w.scrollTop() >= $d.height() - $w.height() - padding) {
        loadMoreData();
    }
});