The director may require, by general or special orders, persons subject to this chapter engaged in intrastate commerce, to file with him, in such form as he may prescribe, annual or special, reports or answers in writing to specific questions, furnishing such information as he may require as to the organization, business, conduct, practices, management, and relation to other persons, of the person filing such reports or answers in writing. Such reports and answers shall be made under oath, or otherwise, as the director may prescribe, and shall be filed with the director within such time as he may prescribe.