Explain the principle of relativity of contracts and give at least two exceptions to the principle and explain.

Ps. I'm a Filipino student and I need help with my assignment regarding my OBLIGATION and CONTRACTS assignment. If you need a referenece of the topic, here's a pdf file of our book (Starting from page 441 entitled contracts).

https://drive.google.com/file/d/1D9GZ3CB8S1TgTQMJAVOcJ4eJkNTHKH-4/view?usp=sharing

I prefer Filipino tutors as much as possible since they already tackled this subject during their college days. Thank you tutors, and God Bless.