How to prevent jquery datepicker from clearing date on submit in jsp

I want to prevent my date from clearing when I hit the search button. I have tried setting form onSubmit to return false still same issue is happening.

<html:form styleClass="form-horizontal" action="refund"
                            method="post" onsubmit="return false">
    <html:hidden property="actionType" />
    <html:hidden property="fromDate" />
    <html:hidden property="toDate" />
    <div class="form-group">
        <label class="control-label"> From Date: </label> <br>
    </div>
        <div class="input-group date form_date" data-date=""
            data-date-format="yyyy-mm-dd">
            <!--mm/dd/yyyy-->
            <input class="form-control border-radius-input"
                onkeypress="return Date1(event);" maxlength="10"
                id="fdate" type="text" placeholder="yyyy-mm-dd"> <span
                class="input-group-addon"><span
                class="glyphicon glyphicon-calendar"></span></span>
        </div>
        <input type="hidden" id="dtp_input2" value="" />
    <div class="form-group">
        <label class="control-label"> To Date: </label> <br>
    </div>
    <div class="col-lg-12">
        <div class="input-group date form_date" data-date=""
            data-date-format="yyyy-mm-dd">
            <!--mm/dd/yyyy-->
            <input class="form-control border-radius-input"
                onkeypress="return Date1(event);" maxlength="10"
                id="tdate" type="text" placeholder="yyyy-mm-dd"> <span
                class="input-group-addon"><span
                class="glyphicon glyphicon-calendar"></span></span>
        </div>
        <input type="hidden" id="dtp_input2" value="" />
    </div>
    <div class="btn-div" style="text-align: center;">
    <button class="btn btn-primary btn-o mr-2" onclick="search()">
    Search</button>
    <input class="clr-btn" type="reset" value="Clear" onclick="clearFields()">
    </div>
</html:form>

and my search function is as below

function search() {
            document.forms[2].fromDate.value = $('#fdate').val();
            document.forms[2].toDate.value = $('#tdate').val();
            document.forms[2].actionType.value = "search";
            document.forms[2].submit();
        }

My declaration for the datepicker is given below

$('.form_date').datetimepicker({
            weekStart : 1,
            todayBtn : 1,
            autoclose : 1,
            todayHighlight : 1,
            startView : 2,
            minView : 2,
            forceParse : 1
        });

Please ignore my div closing syntax as while posting this question I messed up with div closing but html is working fine no issue with it.