$(document).ready(function () {
            $('#leaveTable thead tr')
                .clone(true)
                .addClass('filters')
                .appendTo('#leaveTable thead');
            $.fn.dataTable.moment('DD.MM.YYYY');
            $('#leaveTable').dataTable({
                orderCellsTop: true,
                fixedHeader: true,
                initComplete: function () {

                    var api = this.api();    

                    api
                        .columns()
                        .eq(0)
                        .each(function (colIdx) {

                            var cell = $('.filters th').eq(
                                $(api.column(colIdx).header()).index()
                            );

                            var title = $(cell).text();
                            $(cell).html('<input type="text" style="border:1px solid #EEF1F5;" placeholder="Search" />');                                 
                            $('input',$('.filters th').eq($(api.column(colIdx).header()).index())).off('keyup change').on('keyup change', function (e) {
                                    e.stopPropagation();
                                    $(this).attr('title', $(this).val());
                                    var regexr = '({search})'; //$(this).parents('th').find('select').val();
                                    var cursorPosition = this.selectionStart;
                                    api
                                        .column(colIdx)
                                        .search(
                                            this.value != ''
                                                ? regexr.replace('{search}', '(((' + this.value + ')))')
                                                : '',
                                            this.value != '',
                                            this.value == ''
                                        )
                                        .draw();
                                    $(this)
                                        .focus()[0]
                                        .setSelectionRange(cursorPosition, cursorPosition);
                                }); 
                        });
                },
                pageLength: 50,
                order: [[1, 'desc']],
                columnDefs: [{
                    targets: 7,
                    orderable: false
                }],
            });    
        });

The part in the dropdown figure does not work when searching. Search operation works on other columns.How should I go about it?