How to find out the source of the visit?

Question

Search Engine Optimization

Users from YouTube began to flicker in the statistics of visits.
The fact is that there is only one (in the channel description) link that leads to the main page of the site.
But visits lead to a very deep photo gallery of the site, which cannot be found even from a regular visit to the site (although it is not hidden). and if someone comes it will be buzzing)
Question - how to install the source? Perhaps someone has set a link to our site, I do not rule it out, but how to find the channel from where it leads to us? Referrer only www.YouTube.com

Answer 1

Google search for the full address usually helps.