I'll TRY to help, but I'm NOT A DOCTOR:
A Schmorl's node is the protrusion of the nucleus propulsus (a group of nerve cells) into the spongy part of the vertebra and this has a reactive signal change.
A "signal" is a measure of activity in nerve cells indicated by frequency of discharge.
T11-12 and T12-L1 - Mild disc bulging (no herniation)
L4-5 - mild disc dessication -- this means the disc is drying out. When the disc dries out, it flattens and CAN cause it to bulge, although there is no indication that this disc is bulging.
All other levels are within normal limits.
Impression: Multilevel spondylosis - The actual meaning of this is "any of various degenerative diseases of the spine." So I'm ASSUMING it could be degenerative disc disease (drying out of discs) or a number of things of which you should TALK TO YOUR DOCTOR ABOUT.
This is a GREAT MRI -- what symptoms are you having? Do you have pain, numbness, tingling or anything like that? I sure wish MY MRI looked like this. LOL

If you're having a lot of trouble, get another opinion. Best of luck and God bless. Hugs, Lee