The Job estimates vs Actual Detail report compares the estimated and actual cost and the estimated and actual revenues for each item that you billed.
The Actual Cost is the amount of expenses assigned to a specific customer/job. Inventory isn't going to show a cost until you sell it. This column shows you zero amount for all items used except inventory. There's a possibility that the report shows you all service item except inventory reason why your Actual Cost column is showing a zero amount.
You can double-click the amount of each columns if you wish to know what are the transactions that make up an amount.
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