Some public information (like comments in public groups or mentions) might still be visible through external search tools or manual searching within VK groups, even if the main profile is private [5.6]. draft a more specific message based on why you're trying to reach this person?
There are many websites and apps claiming to bypass these privacy walls. Most are scams. They often require you to log in with your own VK credentials, which can lead to your account being hacked, or they may prompt you to download malware.