It appears that you've read 'perldoc lwpcook' already, which is good. There are two things you need to know to finish this task successfully.

First, you pass CGI parameters as name=value pairs. Think of it like a hash, and you'll have the truth of it.

Second, you only need to know the name of fields and the types of information they contain. You can divine that by reading the page source. For any input, you will likely see a 'name' field. The value of that attribute is the key, and the value you want to assign to that field is the value.

For example:

my $req = POST 'http://www.database.arg', 
    [ subjectspace => 'option 4 default', SubjectDocs => 10,
      txt1 => $text ];
$content = $agent-request($req)->as_string;
[download]

This will give you the resulting page in $content, suitable for saving or printing.