It is possible that he is a relatively new author, or perhaps he writes under a different name.
To find out more about his writings, you could try these steps:
1. Search for him on Goodreads: This website has a vast database of authors and books, and you might find some information about him there.
2. Check Spanish online booksellers: Websites like Casa del Libro or Amazon Spain might have his books listed.
3. Search for him on Spanish literary blogs or forums: These could offer some insights into his work.
4. Check with Spanish libraries: They may have some of his books in their collection.
If you provide any additional details about Jorge Xifra Heras, like a specific genre he writes in, or any publications he might have been associated with, it might be easier to find more information about his work.