Document versions for Vietnamese law

• Extract effective dates and relationships from each document's "Hiệu lực thi hành" article and title, with the evidence quoted. • Rate each finding clear or unclear; apply clear ones automatically and send unclear ones to a reviewer. • Respect the hierarchy of legal documents (a circular can't amend a decree; it can guide it) and end amending documents together with the documents they amended. • Make search date-aware: rank documents not in force on the question's date lower and bring the successor of a replaced document.