Collecting and gathering leads for your business leads via dorking or domain enumeration does not always provide you with valid email list. Here is a technique which might be useful to someone.
lets assume that we want to find email addresses of freelancers from Facebook.
Go to facebook.com and in search enter :
freelancers email comments from left nav menu select posts and when posts appears see which posts have asked for emails, as indicated in this pic.
see posts with max comments and posted emails.
click button to view all comments.
Use chrome addon: Email Extractor https://chrome.google.com/webstore/detail/email-extractor/jdianbbpnakhcmfkcckaboohfgnngfcc to collect and copy all emails from the page.
Voila! Now you have sourced valid emails for your campaigns.