Nevertheless, you will find the following books useful;
* An Engineering Approach to Computer Networking: ATM Networks, the Internet, and the Telephone Network by S. Keshav.
* Mathematical Foundations of Computer Networking by S. Keshav.
* The TCP/IP Guide: A Comprehensive, Illustrated Internet Protocols Reference by Charles Kozlerok.
* The All-New Switch Book: The Complete Guide to LAN Switching Technology by Seifert and Edwards.
* Wireless Networking: Understanding Internetworking Challenges by Burbank et al.
> or books which deal with how networks/protocols work and the theory behind them?
Mostly this (i.e. the latter)
* Foundations of Modern Networking: SDN, NFV, QoE, IoT and Cloud by Stallings.
* Network Security: Private Communication in a Public World by Kaufman et al.
* Web Protocols and Practice: HTTP/1.1, Networking Protocols, Caching, and Traffic Measurement by Krishnamurthy and Rexford.
That should give you an overview of all important aspects of Computer Networking. Each of them is a huge domain on its own and you would need to look up detailed books specific to that domain as needed.