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:
VanEck Funds N-Q filings
VanEck Vectors ETFs:
VanEck Vectors N-Q filings
VanEck VIP (formerly Worldwide) Insurance Funds:
VanEck VIP Insurance Funds N-Q filings