Guys, this is how the hook looks on my search.php file:
<div class="abc search list-group-item" style="background:transparent; margin-top:0;">
<form action="<?php echo osc_base_url(true); ?>" method="get" class="nocsrf" id="secondform">
<input type="hidden" name="page" value="search" />
<input type="hidden" name="sOrder" value="<?php echo osc_esc_html(osc_search_order()); ?>" />
<input type="hidden" name="sCompany" class="sCompany" id="sCompany" value="<?php echo Params::getParam('sCompany');?>" />
<input type="hidden" name="iOrderType" value="<?php $allowedTypesForSorting = Search::getAllowedTypesForSorting(); echo osc_esc_html($allowedTypesForSorting[osc_search_order_type()]); ?>" />
<?php foreach(osc_search_user() as $userId) { ?>
<input type="hidden" name="sUser[]" value="<?php echo osc_esc_html($userId); ?>" />
<?php } ?>
<fieldset style="border:none;padding:5px 0px 0px 0px;background:transparent" class="box location">
<div class="form-group">
<?php if(osc_search_category_id()) { osc_run_hook( 'search_disp', osc_search_category_id()); } else { osc_run_hook( 'search_disp'); } ?></div>
</fieldset>
</form>
and this is the modification on the car attribute search form with the created button:
<form action="<?php echo osc_base_url(true); ?>" method="get" class="nocsrf" id="secondform">
<input type="hidden" name="page" value="search" />
<input type="hidden" name="sOrder" value="<?php echo osc_esc_html(osc_search_order()); ?>" />
<input type="hidden" name="sCompany" class="sCompany" id="sCompany" value="<?php echo Params::getParam('sCompany');?>" />
<input type="hidden" name="iOrderType" value="<?php $allowedTypesForSorting = Search::getAllowedTypesForSorting(); echo osc_esc_html($allowedTypesForSorting[osc_search_order_type()]); ?>" />
<?php foreach(osc_search_user() as $userId) { ?>
<input type="hidden" name="sUser[]" value="<?php echo osc_esc_html($userId); ?>" />
<?php } ?>
<fieldset">
<h3><?php _e('Cars attributes', 'cars_attributes') ; ?></h3>
<div class="row one_input">
<h6><?php _e('Make', 'cars_attributes'); ?></h6>
<select name="make" id="make" >
<option value=""><?php _e('Select a make', 'cars_attributes'); ?></option>
<?php foreach($makes as $m) { ?>
<option value="<?php echo $m['pk_i_id']; ?>" <?php if($make == $m['pk_i_id']) { echo 'selected'; } ?>><?php echo $m['s_name']; ?></option>
<?php } ?>
</select>
</div>
<div class="row one_input">
<h6><?php _e('Model', 'cars_attributes'); ?></h6>
<select name="model" id="model">
<option value=""><?php _e('Select a model', 'cars_attributes'); ?></option>
<?php foreach($models as $m) { ?>
<option value="<?php echo $m['pk_i_id']; ?>" <?php if($model == $m['pk_i_id']) { echo 'selected';} ?>><?php echo $m['s_name']; ?></option>
<?php } ?>
</select>
</div>
<div class="row one_input">
<h6><?php _e('Car type', 'cars_attributes'); ?></h6>
<select name="type" id="type">
<option value=""><?php _e('Select a car type', 'cars_attributes'); ?></option>
<?php foreach($types as $p) { ?>
<option value="<?php echo $p['pk_i_id']; ?>" <?php if($type==$p['pk_i_id']) { echo 'selected'; } ?>><?php echo $p['s_name']; ?></option>
<?php } ?>
</select>
</div>
<div class="row one_input">
<?php $transmission = Params::getParam('transmission') ; ?>
<h6 for="transmission"><?php _e('Transmission', 'cars_attributes'); ?></h6>
<input style="width:20px;" type="radio" name="transmission" value="MANUAL" id="manual" <?php if($transmission == 'MANUAL') { echo 'checked="yes"'; } ?>/> <label for="manual"><?php _e('Manual', 'cars_attributes'); ?></label><br />
<input style="width:20px;" type="radio" name="transmission" value="AUTO" id="auto" <?php if($transmission == 'AUTO') { echo 'checked="yes"'; } ?>/> <label for="auto"><?php _e('Automatic', 'cars_attributes'); ?></label>
</div>
<button style="width:100%;margin-top:5px;" class="btn btn-success" id="subbut()">
<?php _e("Update results", 'sahara'); ?>
</button>
</fieldset>
</form>