Hi Gaurav,
your problem sounds quite interesting. Unfortunately, I don't quite understand it completely. Could you provide some more details about your setup, please? Do you have a client event onClick of the "Pick related" button in the standard relationship grid? Could you share/explain some of the code that you implemented, as well?
If you opened the search dialogue with custom code (and with some onSearchDialog event from a sourcePropertyName parameter that contains your business logic) it should be straightforward to close that window in your custom code as well. Seeing as you have this problem, I assume your setup is different, which is why I'm asking :).
Cheers,
C
