If searching google is to hard for you reading a book is probably gonna be a challenge, let alone designing a system with OOP. There are many (many) times more articles to go off of online, they are also free. If nothing online (which you haven't searched) suits you, a book will never have what you want.
Seriously, if you aren't even willing to search a question this simple and common on Google before asking on a forum (did you find us on Google?), progamming is probably not for you.
I recommend "PHP Objects, Patterns, and Practice, Second Edition", by Matt Zandstra. It's an extremely well-written book which covers OOP fundamentals from a PHP perspective, but also delves into more advanced topics such as design patterns which you'll want to learn more about as your knowledge and experience grows.
Full disclosure, I was the editor on both editions of this book, but don't receive compensation for sales or anything of the sort. It's just a great book, so thought I'd pass along my thoughts.