The Funds file their complete schedule of portfolio holdings with the Securities and Exchange Commission for the first and third quarters of each fiscal year on Form N-Q.
Below are the links to these filings on the SEC's website:
Van Eck Funds: VAN ECK FUNDS N-Q filings
Market Vectors ETFs: MARKET VECTORS N-Q filings
Van Eck VIP (formerly Worldwide) Insurance Funds: Van Eck VIP INSURANCE FUNDS N-Q filings