You've to study the basic materials of xpath (which is not disproportionally big to take too much time) like axes, predicats and all, at least to a survival level before being boggled down on the way by complications associated with any engine, xpath or xquery.
The getXML you got is just the root element and the size() can only be one (1). And then, you use the index i for the sub-query not another index for another Nodes... do you not find it problematic?
In any case, I can show you a direct way to get them all and use your variable getXML as the container to save me some time.
Yes, I agree with g tsuji. You keep coming back here with XPath expressions which appear to be just guessing. Go through an XPath tutorial and learn the language properly. Here's a link to three XPath tutorials which look pretty good to me: