I usually use
each of which like as follows:
One big problem is decomposed into a number of subproblems, each of which implies that blah blah blah.
One day, I came across a word in a book that perfectly matched
each of which. I memorized the word at that time, but now I forgot :-(
If anyone knows this word, please let me know.
I'm not sure but I remember that it was a single word that composed of relative pronoun and preposition, like