[Koha] Bulkimport Authorities and Biblios

Hi I'm migrating my old databass to koha. So far I have managed some steps :-) I have imported authority records and the corresponding biblographic records. I'm not able to search the authority record. They are only displayed as a list if I leave the search field empty, but there are no bibliographic records connected. What do I have to do? Thank you for your hints Beda