When you commit a document like a Sales Order the individual sales order doc type is updated.
You are correct about that!
However, numerous other doc types will be updated as well. Stock quantities will be decremented, for example. If you want to get the broader details of your sales order you need to be able to find all the various affected doc types. Sales orders have many options. The user’s choice of options decides which other doc types are affected.
How do you find them?
What I described to you is the method I use to get the answer to that and many other similar questions.
Companies like SAP, PeopleSoft, etc. have the resources to fully document that sort of question.
ERPNext is a “do it yourself” (DIY) enterprise resources planning system for companies that cannot afford $1200/day/consultant in consulting fees.
(Because of that, much of the documentation you need shows up here in this forum, when members (like you) have a problem, find a solution, then explain what they did. [Solved] What's the right way to version control my customizations? is a good example of this.)
Since presumably you do not have those resources you will have to learn to do your own exploration. What I described is one technique I use. The most important thing is to learn to get your answers from the code base.