I would consider "private news dot com" to be thousands. For the reverse, mid / high hundreds. People appreciate privacy, a business model surrounding "news in private" (private news). For the second domain in question, "talking health dot com" would be thousands, for the casual "talkin", I also see it mid / high hundreds. Talkin may indicate more abstract health content, or aiming to be different, cool or trendy with young people. IMO