How to store or clone the forum?

I have a problem with the forum: it has a huge amount of messages that were migrated from e107, so they give me many problems (for example, I can't use the module "Search".

Then I thought about storing the messages so that they could consult, but they were not in the forum.

I have not found any way to clone the forum to have two, one old and one new.

I also tested the module "Node Convert" to pass messages to the module "Book" (default drupal module), but they lose their structure and all messages are listed without structure, so it is difficult to see.

Any solution?