Meu documento xml parece com .. (é realmente um arquivo kml para o google map ..)

 <kml xmlns="http://www.opengis.net/kml/2.2">
  <Document>
    <Folder>
      <Name>Folder1</Name>
      <Placemark>
        <Name>Placemark1Folder1</Name>
        <LookAt>
          <longitude>-122.0839597145766</longitude>
          <latitude>37.42222904525232</latitude>
        </LookAt>
      </Placemark>
      <Placemark>
        <Name>Placemark2Folder1</Name>
        <LookAt>
          <longitude>-101.083959</longitude>
          <latitude>26.422</latitude>
        </LookAt>
      </Placemark>
    </Folder>
    <Folder>
      <Name>Folder2</Name>
      <Placemark>
        <Name>Placemark1Folder2</Name>
        <LookAt>
          <longitude>-96.566556</longitude>
          <latitude>14.422</latitude>
        </LookAt>
      </Placemark>
    </Folder>
  </Document>
</kml>

De acordo com cada marcador para cada nó de pasta, gostaria de criar um arquivo xml separado, como

1º XML:

<kml xmlns="http://www.opengis.net/kml/2.2">
  <Document>
    <Folder>
      <Name>Folder1</Name>
      <Placemark>
        <Name>Placemark1Folder1</Name>
        <LookAt>
          <longitude>-122.0839597145766</longitude>
          <latitude>37.42222904525232</latitude>
        </LookAt>
      </Placemark>
    </Folder>
  </Document>
</kml>

2º xml

<kml xmlns="http://www.opengis.net/kml/2.2">
  <Document>
    <Folder>
      <Name>Folder1</Name>
      <Placemark>
        <Name>Placemark2Folder1</Name>
        <LookAt>
          <longitude>-101.083959</longitude>
          <latitude>26.422</latitude>
        </LookAt>
      </Placemark>
    </Folder>
  </Document>
</kml>

3º xml

<kml xmlns="http://www.opengis.net/kml/2.2">
  <Document>
    <Folder>
      <Name>Folder2</Name>
      <Placemark>
        <Name>Placemark1Folder2</Name>
        <LookAt>
          <longitude>-96.566556</longitude>
          <latitude>14.422</latitude>
        </LookAt>
      </Placemark>
    </Folder>
  </Document>
</kml>

..eu sou muito iniciante em xml ..ajuda por favor