var currentAddress = window.location.origin + location.pathname;
        $(window).scroll(function () {

         var that = $(this),
         scroll = that.scrollTop() + that.height(),
         target = $(document).height() - $('footer').height()
         ...
         ...
    if (scroll >= target && searchItemLength > searchLimit - 1 && !isPagination && !isLastPage) {
            isPagination = true;
            sample.search.loading.show();
    sample.ajax({
      url: sample.search.createAjaxUrl(sample.search.updateHash())
      }).done(function (data) {
     if (data.paginationData.totalPage + 1 != data.paginationData.currentPage) {
            ...
            ...
            ...
            window.history.pushState(
            currentAddress,
            null,
            (currentAddress + '&page=') + paginationCount);

            ++paginationCount;

var lastScrollTop = 0;
    $(window).scroll(function (event) {
        var st = $(this).scrollTop();
        if (st > lastScrollTop) {
            // downscroll
        }
        else {
            //upscrool
            --paginationCount;
            window.history.pushState(
                currentAddress,
                null,
                (currentAddress + '&page=') + paginationCount);
        }
        lastScrollTop = st;
    });