Surpass is exceed a marked limit, going beyond what is needed. For example, if you pour more liquid than a container can hold, the liquid that does not fit spills. So, we say that you surpassed the amount of liquid that could be put into that container. The love of God exceeds all knowledge, all science, all human understanding, and that love is that God wants us to be overflowing.
The love of God surpasses all knowledge, and this is more than true, because if we reflect on that we understand that God has poured out His love for us without deserving it. He has loved us with such a sublime love that we were amazed at that.