How allow to the Search engine to index Multiple language with one main URL in Codenigiter

I know Search Engine index only one language from website which has multiple language with one main URL. Is it possible to allow Search Engine to index all languages with different methods. i have this URL in English.

http://www.example.com/product/category/2/wires

and this URL in German

http://www.example.com/product/category/2/Drähte

but google only indexed the English URL. So. How to index this two URLs?