"from you": This refers to counsel, viz. (Nachum 1:11) "From you has gone the counselor."
"between blood and blood": between the blood of niddah (menstruation), the blood of zivah (vaginal discharge) or the blood of childbirth.
"between law and law": (questions of adjudication of) monetary laws, capital laws, and the laws of stripes.
"between plague and plague": (questions concerning the cleanliness or uncleanliness of) plague-spots in men, houses, and clothing.
"things": These are (questions concerning) assessments, dedications, and consecrations.