In filtering for an "exact expression" I see that RSSOwl gives me "exact" or "expression" instead of only "exact expression".
What am I doing wrong?
That's how RSSOwl's search works, you are not doing anything wrong.
For example: I'd like to only filter "division of labor" and using this expression I get articles with DIVISION or just with LABOR.
Is there any way to get just the ones where the expression "DIVISION OF LABOR" appears?
As far as I know the only documentation on the search feature can be found here: http://www.rssowl.org/dl/videos/search/search.html