WordPress: search form
<form method="get" name="searchform" action="<?php bloginfo('url'); ?>/">
<input type="text" value="" name="s" placeholder="Поиск" />
<input type="submit" name="Поиск" value=""/>
</form>
<input src="<?php echo get_template_directory_uri(); ?>/img/search.png" value="submit" type="image">