Hi,
I tried to search for “Arabella” in the portfolio editor, in spanish language, because that was one of the items with issues. I found, that there is actually 2 of “Arabella”, and one of them is not working. Please try look for “arabella” like this, and click on it’s permalink, it will lead to a non-existing page.
The plugin only returns these items, but unfortunately there is some sort of issue with them. Removing these duplicates should resolve the issues.