Hi Prasetio30, Happens to me on a rather frequent basis. My Thomas the Tank Engine articles get used in reviews the most frequently (and I mean copied EXACTLY word for word). I think, guessing by your posts, that you aren't sure how to contact the websites who are using your content. If so, do the following:
1. Go to "my account" and click on the article that has been flagged.
2. Click on the highlighted link that states "COPIED: The content of this hub may have been copied on another site".
3. You should now see a highlighted list with links to where you hub has been copied (there may be more than one site listed).
4. Click on the highlighted links and verify it is a copy of your hub. Many sites offer a way at the end of the "offenders" article that says "report this article" or something like that. If they have this, simply report the hub as being copied from your original article.
5. If there is no way to notify the website that they have copied your content, go back to your hub and the highlighted list. You'll notice that there is a link under "DMCA" that says "file". Click on the word "file" and it will provide you with a formal letter that can be sent to the website administrator.
Unfortunately, in most of my cases, no website administrator or contact information can be found. I could chase my tail trying to smack down these lazy writers (checking whois files, etc.), but it seems to be a waste of my time.
I wish HubPages used Copyscape or something similar that we could put in our posts. Has anyone out there put Copyscape warnings in their hubs?