Header cart link – localisation

Hello,
I am using WooCommerce together with the Memorable theme with the Header Cart Link feature enabled (cart displays in my primary navigation).

I am using the Slovak localisation for woo commerce, however the “item; items” text in the menu stays in english. I have tried changing it in the theme-woocommece.php:
<a class="cart-contents" href="<?php echo $woocommerce->cart->get_cart_url(); ?>" title="<?php _e('Košík', 'woothemes'); ?>"><span class="count"><?php echo sprintf( _n('<span>%d</span> item', '<span>%d</span> items', $woocommerce->cart->cart_contents_count, 'woothemes' ), $woocommerce->cart->cart_contents_count );?></span></a>
However changing it there did nothing. I also tried the Codestyling Localization plugin where I tracked down the %d item, but even after changing it there it stayed in english.

Any ideas what could be the problem and how to translate the item / items in the header navigation, please?

Thank you, any help is very appreciated!

https://wordpress.org/plugins/woocommerce/