Fetch all the material no from MARA table
And Pass it to RESB table,
IS the material is not passed into RESB Table, Then you can consider that material is not used for production.
If the material is passed into RESB table, Then You can Filter out the data for the Current Month, and sum up the field Quantity Withdrawn, If the Sum up value is "0", then you can consider that material is not used for production