function AjaxReportRefresh() {
    var page = (isAdvanced ==  0 ) ? "3" : "4";
    var arg_name = (isAdvanced ==  0 ) ? "P3_HDN_SEARCH" : "P4_HDN_SEARCH";
    var arg_val = $v('P2_TXT_SEARCH');
    var search_param = {
        p_flow_id:      $('#pFlowId').attr("value"),
        p_flow_step_id: page,
        p_instance:     $('#pInstance').attr("value"),
        p_request:      "",
        p_arg_name :    arg_name,
        p_arg_value :   arg_val
    };

    if (isAdvanced ==  1 ) {
        search_param.x01 = $('input:radio[name=radio_sektor]:checked').val(); //сектор
        search_param.x02 = $('input:radio[name=radio_deleted]:checked').val(); //состояние
        if ($('#chk_tech').is(':checked')) {
            search_param.x03 = ''; //технология
            $('#technology_checkboxes :checked').each(function() {
                (search_param.x03 != '') ? search_param.x03 += ', ' + ($(this).val()) : search_param.x03 += ($(this).val());
            });

        }

        if ($('input#chk_tp').is(':checked')) {
            var tp_conf = {};
            tp_conf.ap = {
                operator:   $('select#select_tp_ap').val(),
                value:      $('input#txt_tp_ap').val()
            };

            tp_conf.rp = {
                operator:   $('select#select_tp_rp').val(),
                value:      $('input#txt_tp_rp').val()
            };

            tp_conf.duration = {
                step:   $('select#select_tp_duration').val(),
                value:      $('input#txt_tp_duration').val()
            };

            tp_conf.unlim = {
                world:  $('input:radio[name=radio_unlim_w]:checked').val(),
                tasix:  $('input:radio[name=radio_unlim_t]:checked').val(),
                sarkor: $('input:radio[name=radio_unlim_s]:checked').val()
            };

            tp_conf.onlyThese = $('input#as-values-tp_ids_inc').val();
            tp_conf.noneOfThese = $('input#as-values-tp_ids_exc').val();

            search_param.x04 = JSON.stringify(tp_conf);
        }

        if ($('#chk_abongrp').is(':checked')) {
            search_param.x05 = ''; //абонгруппа
            $('#abongroup_checkboxes :checked').each(function() {
                (search_param.x05 != '') ? search_param.x05 += ', ' + ($(this).val()) : search_param.x05 += ($(this).val());
            });

        }

        if ($('#chk_else').is(':checked')) {
            var else_conf = {};

            else_conf.c_ids ={
                from: $('input#txt_c_id_from').val(),
                to:   $('input#txt_c_id_till').val()
            };

            else_conf.saldo ={
                operator: $('select#select_saldo').val(),
                value:    $('input#txt_saldo').val()
            };

            else_conf.opers = $('input#as-values-oper_ids').val();
            else_conf.ats = $('input#as-values-ats_ids').val();
            else_conf.ip = '';
            $('.ip_octet').each(function() {
                else_conf.ip += ($(this).val()) + '.';
            });
            else_conf.ip = else_conf.ip.substring( 0 ,else_conf.ip.length- 1 );
            else_conf.discount = {
                operator: $('select#select_discount').val(),
                value:    $('input#txt_discount').val()
            };

            search_param.x06 = else_conf;

        }
    }
//    alert(JSON.stringify(search_param));
    $.post("wwv_flow.show", search_param, function(data) {
        var startTag = '<ajaxReport>';
        var endTag = '</ajaxReport>';
        var start = data.indexOf(startTag);

        if (start >  0 ) {
            data = data.substring(start + startTag.length);
            var end = data.indexOf(endTag);
            data = data.substring( 0 , end);
        }
        $('#AjaxReport').html(data);
        $('#pFlowStepId').attr("value", page);
        $('#closeReport').click(function() {
            $('#AjaxReport').html('');
        });
    });
}

function advanced_search(search_in in varchar2) return varchar2 as
    l_sector varchar2( 40 );
    l_ret varchar2( 32000 );
  begin
    execute immediate 'alter session set NLS_SORT=BINARY_CI';
    execute immediate 'alter session set NLS_COMP=LINGUISTIC';
    l_sector := wwv_flow.g_x01;
    l_ret := 'search_in:' || search_in || ', sector: ' || l_sector;
    return l_ret;
  end advanced_search;

Параметры application/x-www-form-urlencoded
p_arg_name	P4_HDN_SEARCH
p_arg_value	
p_flow_id	 102 
p_flow_step_id	 4 
p_instance	 1902434046761268 
p_request	
x01	- 1 
x02	- 1 
Исходный код
p_flow_id= 102 &p_flow_step_id= 4 &p_instance= 1902434046761268 &p_request=&p_arg_name=P4_HDN_SEARCH&p_arg_value=&x01=- 1 &x02=- 1 

$.ajax({
            mode: "abort",
            dataType: 'html',
            url: "wwv_flow.show",
            data: {
                x01: some_value,
                x02: some_value,
                p_flow_id: $("#pFlowId").val(),
                p_flow_step_id: $("#pFlowStepId").val(),
                p_instance: $("#pInstance").val(),
                p_request: 'APPLICATION_PROCESS=SOME_PROCESS
            },
            success: function(data) {
                //do smth here
            }
        });

                  var options = {
                        appProcess: 'SOME_PROCESS',
                        dataType: 'html',
                        x01 : some_value,
                        x02 : some_value,
                        success:function(data) {
                            //do smth here
                        }
                    };
                    $.jApex.ajax(options);