There is a new enhancement that allows users to search for Contacts without knowing the Company Name as per the below screenshot example:
Search by Contact Name (not by company name) in the Case List/Contacts Tab (as per the below screenshot example):

This feature is also available when creating a new case in the new Case Wizard under the 3 below sections:
​Employer Contacts search in the Employment details section (as per the screenshot example below):

The Referrer Contacts Search in the Referral details section (as per the below screenshot example):

The Bill to Company Contacts Search in the Bill to Company section (as per the below screenshot example):