Enter a search argument in the first field

What causes this issue?

No entry was made in the first field.

How to fix this error?

Enter a search term in the first field. The search will only be
started when you have entered a search term. This entry is necessary
to avoid excessive search time.

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

Error message extract from SAP system. Copyright SAP SE.