help need in the perl script that create one xml file form multiple files.

Hi every one,
Please excuse me if any grammatical mistakes is there.
I have multiple xml files in one directory, I need to create multiple XML files into one XML file.example files like this</p>

      file1:bvr.xml

    <?xml version="1.0" encoding="UTF-8"?>
    <specification xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
     <details>
     <name>johan</name>
     <address>Langgt 23</address>
      ---more info---
     </details>
    </specification>

     file2:kvr.xml

     <?xml version="1.0" encoding="UTF-8"?>
     <shiporder xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
     <details>
     <name>venu</name>
     ---more info---
     </details>
     </specification>

       file3:svr.xml

     <?xml version="1.0" encoding="UTF-8"?>
     <shiporder xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
     <details>
     <name>kent</name>
     ---more info----
      </details>
      </specification>

      file4:tvr.xml

     <?xml version="1.0" encoding="UTF-8"?>
     <shiporder xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
     <definition>
     <name>kent</name>
      ----more info---
      </definition>
      </specification>

I need to create one xml file like this.

           new.xml 

    <?xml version="1.0" encoding="UTF-8"?>
    <specification xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
     <details>
     <name>johan</name>
     <address>Langgt 23</address>
      --more info--
     </details>
   
     <details>
     <name>venu</name>
     ---more info----
     </details>
     
     <details>
     <name>kent</name>
     <address>vadrss 25</address>
     ---more info--
      </details>
      
       <definition>
     <name>kent</name>
      ----more info----
      </definition>
    </specification>

I tried like this But I have some problems with this script.

    #!/usr/bin/perl
      use warnings;
      use strict;
     use File::Find;
       use XML::LibXML::Reader;
     use Data::Dumper;
      my $Number;
   
      my $dir="C:/file/sav";
      find(\&wanted, $dir);
      sub wanted() {
           if ( -f and /(\.xml)$/) {# find all the files with a suffix of .xml

      my $reader = XML::LibXML::Reader->new( location =>$_ )
     or die "cannot read file.xml\n";
 
        while ($reader->nextElement( 'details' ) ){
                                                                                                                         
              $Number = $reader->readOuterXml();

			  print "$Number\n";	
                 } 
 		 
             }
       return;                   
      }

but I have two problem in this script

1) I am extracting information from all XML files Having "details" Node element, But in one XML file I have data with some other Node element "definition" I am not extracting that information, What should I do if I want to extract that information and store in the same variable.

2) After extracting all information That is stored in a $Number varible, I want to store that $Number variable information in one XML file how can I do that one. Please help me.I am very new to perl.

                    \(or\)

Is there any other ways to combined all XML files data into one XML file.