Yes, I think you have BP objects missing. In the search the name fields are sourced as follows:
| NAME_LAST | BUT000 | BP |
| NAME_FIRST | BUT000 | BP |
In customising (SPRO) for Personnel Management, under Organizational Management -> Integration -> Integration with SAP Business Partner, check whether the HRALX HRAC switch is activated.
If you activate the switch after central persons have been created in your system, you need to regenerate the business partners for the existing central persons. You do this using the Synchronize Employees - Business Partners (HR_SYNC_PERSON) program.
And of course, ensure indexing completes before testing search (details panel should work immediately).
Stephen