Chinese knots are made of various colors of threads Chinese knots are made of various colorful threads Both are correct, but they have slightly different meanings. "Various colors of threads" means any color, so this would mean the threads could be any color. However, "colorful threads" means the color of the threads has to be colorful (synonym: bright) so colors like red, pink, purple, green (not colors like gray, black, white, dull ones like such). Hope this clears things up, message me if you need any more help!

Chinese knots are made of various colors of thread (not threads) Chinese knots are made from colorful thread (not threads) Thread can be a countable noun but usually not. I think that "thread" should not be a countable noun when used in this context. We often say "strands of thread" to describe the construction of something like a Chinese knot.