On the Admin Console > Users & Groups > External Users, allow users to use a wild card for searches. Currently, the search only performs a "starts with" search on the email address and name. However, this is very limiting and restrictive, especially when we have thousands of external users, and the name field is variable (first last; last first; nicknames, etc.) The wild card feature or "contains" would give the user an option to search within the email address to filter users by email domain.