Atanu,
You are right, I have done the same on method /IWBEP/IF_MGW_APPL_SRV_RUNTIME~GET_EXPANDED_ENTITY and yet not getting the table in the final output (same attachment).
In debug mode i could see the table populated with 6 entries but on the output as you see the table is not even displayed. The URI goes like this -- /sap/opu/odata/sap/ZPP_PRODOPS_CONFIRM_SRV/ProductionOperationConfirmations('0000000357')?$expand=GoodsMovements
And also can i achieve the expected result directly for my URI: /sap/opu/odata/sap/ZPP_PRODOPS_CONFIRM_SRV/ProductionOperationConfirmations('0000000357')?????