CD74HC4067- reading serial data from rfid

Hello, I’m trying to connect 4 id20la rfids o arduino, and after hours of issues, i’m trying to do it through this little giuy. anyone can help me with how can i read serial data from rfid?

I’m searching internet, but everyone is talking about reading analog inputs, but no one is talking abput serial reading…

check this article:

http://bildr.org/2011/02/cd74hc4067-arduino/