It is supposed to print the line when all of the vowels are present. The Deparse module seems like a good idea, except it missed the one expansion step that I was missing. I had this:

$line =~ (/a/i && /e/i && /i/i && /o/i $$ /u/i)
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What i needed was:

($line =~ /a/i && $line =~ /e/i && $line =~ /i/i && $line =~ /o/i $$ $
+line =~ /u/i)
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The deparse did not show all of these individual matches with the built in $_ ($line in my example).