I am looking at getting a output of all the specification and the material associated with the specification.
I tried to join table ESTMJ and EHTRH to do this but this somehow doesn't get the desired output.
Any help on this would be highly appreciated.
Not sure what you mean by not desired output. Too many lines, or not displaying the expected result. Are you using CG02 search or using ABAP/SAP query? Think you already inner join the RECN column for the two tables.
Maybe you need also to check if you filter out those marked deleted.
Please try to add the delete indicator in your query, and only show those not marked as "X".
Hope this can help.