If you particularly want a single regular expression, you can get it by using lookahead:

  my $re = join ' ', map "(?= .*? \Q$_\E)", @ARGV;
  if ($entry =~ /^ $re/sx) { ... }
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That would turn your example arguments into something like:

  m{ ^ (?= .*? bill ) (?= .*? clinton ) }xs
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so it matches if:

from the start
  fail unless we can find some characters followed by "bill"
_and_ (still from the start)
  fail unless we can find some characters followed by "clinton"
succeed
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I'm not sure how efficient that is, but it should be ok; if speed is important it would be worth benchmarking against some alternatives. Don't forget that when looking for an exact string match, index() can be faster than m/\Q$str\E/, and that if you're going to match one string against many regexps study($string) can help.

Hugo