woocommerce eMails translation strings not used

Hi there,

I use the german informal version for translations.
Sending Mails i.e. order completed, does not make use of the string I translated with codestyling localisation
There is i.e. this one
<?php printf( __( "Hi there. Your recent order on %s has been completed. Your order details are shown below for your reference:", 'woocommerce' ), get_option( 'blogname' ) ); ?>
In codestyling I go to the woocommerce plugin and select the informal (“Du”) and translated it to some german text. In the textdomain dropdown I see “woocommerce” so same as seen in code above. I also pushed the create mo file button successfully.
But the mails which are sent still have some other german translation string which I can not find anywhere.

Is there a way to find out, which mo or po file is really used by WP, may I have a mess in my translation files?

Thanks for help
Tom

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