Your best option may be to find a source with better quality books (If you bought them, complain to the publisher, if they're public domain, reupload to the site after fixing them. I'm assuming for the sake of your conscience that you didn't pirate them.).
If you can't or don't want to do that, I'd advice you to use the search & replace function found within the conversion settings, chances are that you'll have to adapt the search expression for every book, though. Just to get you started, your example "I like...like books" could be rectified by using a search expression like
and replacing that with
There's
a beginners level tutorial for regular expressions available, should you need it.