How to find out the source of website traffic, knowing SimilarWeb data?

Question

Search Engine Optimization

Good afternoon!
I have the following question, I analyze the site of interest to me through the similarweb service, I see in the traffic sources (refers) a selection of sites from which there are a large number of transitions, I go through them in turn - there may be a forum, a blog, etc., with a bunch of sections, pages , subdomains, etc.
When studying the site from which there were transitions, I do not see any links or advertising to the site of interest to me point blank. Question:
How to analyze the sites from which the transition occurs and find the source (page?) with the link on which the transitions to the site of interest go, and is it possible. Thank you!

Answer 1

Do you have Premium or Custom package?
there the lists are somewhat different
+ the similarweb method works in such a way that not everything that traffic sources are traffic sources

Answer 2

find a source (page?) with a link that leads to the site of interest

For example, take Ahrefs, open the data on the site of interest there, go to the "Outgoing links" section and look for the desired domain. Or vice versa, open the data on the site under study and look in the "Backlinks" or "Referring domains" section for the source you are interested in.