after move term1 from Voc-A to Voc-B, no content attach on term1

From the Double Tree interface, I move term1 from Vocabulary-A to Voc-B, after done that, I create a view to list all the content from term1, but showing 0.

I then move the term1 back to Voc-A, then all the related content are showing in views.

I am wondering am I missing something for move the terms between the vocaulary ? please advise. Thank you