Thanks for your request. You should note, bullet is not just a simple text it is a property of a paragraph. And if you would like to copy bullet to another document you should copy whole paragraph.
Regarding DocumentExplorer it is just demo project which helps you to inspect structure of your documents.
Please see the following link for more information: https://reference.aspose.com/words/net/aspose.words/paragraph/listformat/
Best regards,