Cookie problem

[eluser]sojic[/eluser]
This code "do not write" cookie

Code:

if ($this->input->post('search')) {
            $keyword = urlencode($this->input->post('search'));    
            set_cookie('search', $keyword);
        }
        else {
            $keyword = $this->input->cookie('search');
        }

Also I try

Code:

$keyword = get_cookie('search');

I have autoload "cookie" helper.