All you have to do is to google for: "<your domain> <spam keyword>"
Alternatively, you could try: "site:<your domain> <spam keyword>"
I guess everybody knows what keywords that most spammers would use. A very obvious example would be "porn". So, I search in Google for "enrii.com porn". In the search result, I found one of my page links to a porn site. As I opened the page, I can't see the word.
Using Ctrl-F on Firefox, it seems to be able to find the word, though it is not visible. Then, I looked in the source file (right-click > View Page Source), and I found a long list of links after blog content. The spammer hide the links with the following CSS:
Obviously, it is done for the search engines, not for my visitors. I have removed it. You should do the same for your blog. You should also try on different keywords.
Though it's interesting that this trick actually helps you to removed unwanted spam on your blog, I wonder why it would work as the page could have been removed from Google's search results if it contains spams.
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