View the BOM of a product that I do not produce but procure

Dear community,

Would you please have the pleasure to help me with the following?

For the product that I produce, I can successfully review its BOM by maintaining correctly the SOURCEPRODUCTION and PRODUCTIONSOURCEITM MDTs. Now, I would like to be able to review the BOM of a product that I don't produce but I procure. How could I do that?

I tried to first maintain the PRODUCTIONSOURCE of that product, by setting a SOURCE ID (as usual) and SOURCETYPE=U.

After that, I also maintained the SOURCELOCATION MDT, so that they system knows from where I procure this product. (quotas included)

Finally, I also maintained the PRODUCTIONSOURCEITM where I model the components of that product. However, the BOM is not finally revealed in the system.

On web I read that the PRODUCTIONSOURCEITM master data type is not relevant for an external source of supply. What that would mean ?