Since you mention a social security card, I'm assuming you're American; I'm also assuming you're of legal age.
You could simply contact the appropriate government offices, tell them your parents won't give these documents to you and you're finding it difficult to get along without them. For example, a social security card is required to get a job.
Or, you could raise the stakes and turn the tables on them; tell your parents that if they won't hand over the documents you're going to the Social Security / Passport office and report them stolen -- by them. That won't endear you to your parents, but it ought to shake their tree. They need to learn, sooner or later, that they are not in control of your life. But be prepared for them to go ballistic.