Software » Web » Redmine plugins » Scrum

Hi,

I create PBIs in the Product Backlog.
Now I must create new PBIs in the "Product backlog items" col of the Sprint board.

What are the different btw PBIs in the Product Backlog tab and the Sprint tab/Sprint board?
Can I show the PBI created in the Product Backlog tab into the "Product backlog items" col of the Sprint board?

I can move PBI in the Product backlog to the Sprint board. But the PBI in the Product backlog is removed.
How can I keep PBI in the Product backlog event moved to the Sprint board?

I appreciate it if anybody could help me to explain.