There's a "report to moderator" function on the bottom right of every post, you can use it to report posts that are off topic to your thread (as this self advertisement post would be).
If that doesn't do enough for you, consider closing your thread and starting a new, self-moderated one. Then you can be the one deleting posts irrelevant to the topic.
I found those about the report how to start a self moderated thread i will lock my old thread to avoid further problems, thanks.