I started posting this as part of another post but realized it's a fundamental issue for those of us with DID. How do you find out things that other alters may know but you don't?
For us, the process is often: be calm, receptive, open....pose the question, listen, wait for knowledge to come. Journaling has generally been like this but not always necessary. We come to know stuff without knowing how we know. I once assumed everyone's mind worked like that.
Sometimes the knowledge just floats up, source unknown, but I'm better at sensing whether it's from inside or just me guessing, filling in the gap. My guesses have less depth, less staying power. There's little sense of certainty in my own guesses, but I have to pay attention to all that. Actually I think I developed that awareness long ago, maybe in childhood.
I've learned to be patient. The one with the answer may not be around or want to engage. Several of us are very hurt and withdrawn. It's like I launch a computer program in my head that runs and returns an answer when it finishes running. Sometimes it's immediate, other times not.
Some of the searching is about outside stuff. So I can't find my phone or my keys and ask inside if anyone has a clue. Someone inevitably has something.