how to highlight partial searchwords?

I have just installed Search Hilite and it is working very nicely for the most part. But it only highlights a complete word.

For instance, if I search “pickle” on my wordpress, any instances of the word “pickle” are highlighted, but the pickle in “pickled” is not – even though one of the posts that is found only has the word “pickled”.

Does anyone know how I can alter the coding and/or what search terms I should use to find out how?

Thank you.

(I also looked at wp-highlight and see that it gets the same results.)