Use this code example to change the "search_contains" setting to false. By default, this is set to true in Formidable. When it is false, searches will only show results that begin with the search query. When set to true, anything that matches the search anywhere in the string is returned instead.

add_filter('frm_chosen_js', 'chosen_js');
function chosen_js( $opts ) {
	$opts = array(
		'allow_single_deselect' => true,
		'no_results_text'       => __( 'No results match', 'formidable' ),
		'search_contains'       => false,
	);
	return $opts;
}