The director may do any of the following:
(a) Administer oaths and take testimony thereunder.
(b) Issue subpoenas which require the attendance of witnesses before him, together with all books, memoranda, papers, and other documents, articles, or instruments.
(c) Compel the disclosure by such witnesses of all facts which are known to them relative to the matters under investigation.
(Enacted by Stats. 1967, Ch. 15.)