This is a simple works demonstrate that everything inside blockchain is actually public and you have to avoid putting your sensitive data inside it. Please avoid putting your sensitive data on private objects in solidity and I would be so happy if you refer to the article in the following link https://medium.com/@taberandwords/writing-a-useful-smart-contract-7a36c72ea130 On this article I better explained how this project works and what are the keys of writing a good contract. I know there are more things to add but new tutorials will come soon.