This rise so much doubt because it is difficult to verify but it seems as those yarns are 3stranded and that indicates that a ropewalk had been employed what we understand very well for a production of 30 kilometers

Can you repeat this sentence, but add in punctuation?
This rise so much doubt, because it is difficult to verify, but it seems as those "yarns" are 3-stranded, and that indicates that a ropewalk had been employed. (what we understand very well for a production of 30 kilometers).