Help making block break like vines

Hi, I made a mod element-block as a custom vine. I need help with making it break like vanilla vines do. That is, when the block "behind" the vine is broken, the vine block breaks. I have attached my attempt but really have no idea how to have it check the block "behind" the vines state. If I can tell it what block I can make it break "that" block easily. 

https://imgur.com/a/eLZzqYx