Multiple languages

I am about to release a photobook about the Carnaval de Barranquilla in Colombia. Most of the texts in the book are spanish, german and english. Just one text is only available in spanish.

I noticed, that I have to set a language for the book in iTunes Producer and that I can only choose one language. Which language do you think I should choose? Spanish as it is the language mostly used in the book and many customers might be from Colombia? Or english to catch the international customers.

I have the same question for the book description. Is there a way to use different languages for different stores? Can I use multiple languages in the description? Or do I have to stick with one language? If I have to stick with one language, which one would be the best?

Thanks!

Bernd