Use a regex to match a character class and assemble the result using a join. This has the advantage of normalising multiple underscores (or whatever was excluded by the character class) while preserving the original string. 
my $found = join ' ', $string =~ /([^_]+)/g;
print "$found\n";

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In reply to Re: a small regexp question by inman
in thread a small regexp question by newroz

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