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When you click on "search item" a menu will appear on the left-hand side; while via the "add uncodified" button you can add items not included in the MSF Supply's offer, the drop-down will allow you to show the catalogue, and - if any - the standard lists and forecast:. The icon 
allow to inject the full content of a selected list (standard list or forecast).
Then you can fetch items in the tree-style menu and add them to your content via the pop-up:
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