When you're viewing inventory on the Consignment tab, without having a consignor selected you will not see a specific consignors inventory but a list that includes all your consigned inventory. To only view a specific consignor's inventory select them by clicking on their name.
Whether or not you choose to search all consignment inventory or a particular consignor, you can search through the inventory using the filter bar.
Using this bar you can choose to only search for items in a particular category, items of a particular status, items within a particular start or expire date range, by tag color and you can a enter a brief description of an item in the Item field. You can even type in or scan a SKU into the Item field to bring up a particular item. You can use multiple fields to narrow your search results.
The "Show Old Items" checkbox will reveal items that have been sold for more than 30 days. It will show you items you have donated, returned to customers, and even items converted to store inventory. This feature helps to show you the items that get hidden as you usually won't need to see them on a daily basis.