When a domain is privacy protected, it means that the domain owner opted to use a privacy service (eg: whois guard) offered through their current registrar. All privacy services are a third-party service that replaces the domain owner's personal information with their third-party information in Whois records. Domain owners may opt to use privacy protection so that they can remain anonymous.
When a domain is privacy protected, you have no way to contact the domain owner directly. You may contact the privacy service provider at the email provided in the Whois record for information pertaining to further contacting the domain owner. You may also visit the privacy service providers website in order to contact the registrant.