Interesting, it looks like you can only get your own data, if you have an American postal address. So if you moved abroad (or never lived there), you can not get your data, even if they have it.
If you worked for American companies from abroad, you probably filed W-8BEN and were considered a non-US person for all tax purposes, had no TIN and nothing was reported on you to Equifax or other credit reporting companies (e.g. Transunion or Experian).
If you filed W-9 as US person, you gave them a TIN, which in the majority of employment related cases is your SSN, and then they most likely reported your employment to Equifax.