I'm stuck with XPath query that I'm trying to do. I want to count all fish during certain moon. For full moon, query should return 2(there are 2 fish during that moon) My current query is this: `count(//fish[//moon="full"])` . What's wrong here? It counts all fish instead of only 2.

XML is as follows:

```
<winterfishing>
<week number = "3">
   <moon>full</moon>
   <catch>
      <fish>
         <species>bass</species>
      </fish>
      <fish>
         <species>pike perch</species>
      </fish>
   </catch>
   <moon>
</week>
<week number = "4">
   <moon>half</moon>
   <catch>
      <fish>
         <species>perch</species>
      </fish>
   </catch>
   <moon>
</week>
</winterfishing>

```