woocommerce translate !!!

I have a Dutch website and would like to translate some rules. In produckten you can choose from a number of options and that line I translate in dutch. Similarly, if you have ticked all the options there in English “clear selection” also in dutch I want to change this rule. And the cart eg if no produckten able all in English. all this I would like to change in dutch. Where can I change that, which file? Who can help me I’m looking for so long. thanks

http://wordpress.org/plugins/woocommerce/