To clarify. I'm not the orginal poster but I got the same problem. 
my $tree = HTML::TreeBuilder->new_from_content($webcrawler->content())
+;

if (my $div = $tree->look_down(_tag => "article" )) {
         print $div->as_text(), "\n";
     } else {
         print "Not found";
        }

[download]
This piece of code gives a "Not found" on this article: http://www.sueddeutsche.de/politik/thailand-regierungschefin-yingluck-verliert-ihr-amt-1.1953299 although there is an article tag To test the code I changed it to grab a piece in the article tag itself: 
if (my $div = $tree->look_down(_tag => "p" , class=>"article entry-sum
+mary")) {
         print $div->as_text(), "\n";
     } else {
         print "Not found";
     }

[download]
It worked as expected and printed me "Das höchste Gericht in Thailand hat entschieden: Regierungschefin Yingluck Shinawatra ist des Verfassungsbruchs schuldig. Sie wurde sofort ihres Amtes enthoben. " So I can't seem to grab the article tag itself. Since article is an html5 tag this might be the problem but how can I solve this another way?

In reply to Re^2: HTML::Treebuilder look_down not working with <header>, <article> etc by Anonymous Monk
in thread HTML::Treebuilder look_down not working with <header>, <article> etc by Anonymous Monk

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