Annotate the selection field with @ObjectModel.foreignkey.association.
Association for a field can be used as a check table for the field. Define value help dialog by reference an association with foreign key relationship.
It is important to association. Normally, only technical key fields of a business entity have the association to other views. In the search help window, only the key field and one field annotated with @semantics.text:true can be displayed in the search result window.
@Consumption.valuehelp: ‘<association_name>’ to annotate the selection field for value help.
Steps to create modeled value help CDS view