Get terms child of current category

Hi guy’s

For build an isotope filter, I try to get the terms of the childs for the current category page.
I can get all the categories of my website, but not the child of the current category.

Someone can help ?
Thanks

<?php
	$terms = get_terms('category');
	$count = count($terms);
	if ( $count > 0 ){
		foreach ( $terms as $term ) {
			echo "<li><a href='#' data-filter='.".$term->slug."'>" . $term->name . "</a></li>\n";

		}
	} 

?>