One possible approach:

>perl -wMstrict -le
"my @terms = qw(january foo february egypt moon saturday bar);
 my $search = qr{ @{[ join '|', @terms ]} }xms;
 my $str =
  'in february the moon is not visible in egypt on saturday night';
 my %count;
 ++$count{$1} while $str =~ m{ ($search) }xmsg;
 for my $term (@terms) {
   print qq{$term is }, $count{$term} ? '' : 'NOT ', 'present';
   }
"
january is NOT present
foo is NOT present
february is present
egypt is present
moon is present
saturday is present
bar is NOT present
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