When you're about to quit a job, an Institute and so on. They need to make sure that you didn't owe them anything, so they give you a document with a list of people you need to ask for sealing your document. So you take it and go around to all those people and ask them to seal your document, once you have all the seals, you're free to go your way.

Here's we come to the origin of the word, derived from the verb обходить which means to go around some place