Highlighting search results

When I view a PDF document that has been matched from a search, DTPro highlights all instances of the search term regardless of whether they are partial matches or not. It does not do this with text documents, only PDFs. Is this a bug or expected behaviour?

For example, if I had a PDF that I save out of TextEdit that contains the text:


And I search for “for”, the highlighted result looks like this:

If I create a plain text note containing the same data it looks like this:

Initially we thought the problem was actually with the matching, but it seems that it’s just highlighting. If I create a PDF of some text containing just the word “enforcement”, that document is not matched with a search for “for”.