You could write a script(i would use perl) to get every keyword on the page, 10 words before it and 10 words after it. Then output as new line in a file. I guess you could do it in less than 15 lines of code.
If I could write the script off the top of my head I would but I can't write an original line of code in perl. Despite that I have come up with perl scripts that do similar harvesting/mining just by loading dozens of mini-tutorials off google then mixing and matching to get what I want. Sounds complicated, but it is very easy to do, just find the first tutorial with code that does something even remotely related.