add_action('job_bm_job_archive_search_form','job_bm_job_archive_search_form_new_field');
function job_bm_job_archive_search_form_new_field(){
?>
<div class="option">
<input placeholder="<?php echo __('New Field', 'job-board-manager'); ?>" name="new_field" type="search" value="<?php if(!empty($_GET['new_field'])) echo sanitize_text_field($_GET['new_field']) ?>" />
</div>
<?php
}