[Orgmode] `org-refile' doc string

[Štěpán Němec]

In the documentation of `org-refile' we read:

  If there is an active region, all entries in that region will be moved.
  However, the region must fulfil the requirement that the first heading
  is the first one sets the top-level of the moved text - at most siblings
  below it are allowed.


I completely fail at parsing the second sentence. Could please someone
who knows what it's trying to say fix it?

Many thanks,

  Štěpán