Child of a parent of a child

I have a pretty nasty xml structure at my hand.
I was able to make the query work with http://www.bit-101.com/xpath/

Here is the full path which gives some idea about the structure:
npexchange/article/articleparts/articlepart/article_part_type_id[@id='1']..//data/npdoc/headline

But I cannot make it work with feeds_xpathparser. In some issue I found a tip to use parent:: so I tried
article/articleparts/articlepart/article_part_type_id[@id='1']/parent::articlepart//data/npdoc/headline

I have the /npexchange as context and other queries without the parent-child syndroma work fine.

The problem as you can see is in the structure. I need to get the specific type id from the same level as body and headline.