Bhavna04

I'm in the middle of reading book 2 n I have a doubt when WuBi get to know that SuYu is alive why he didn't go to the SuYu' father to know his whereabouts, and if SuYu's father said to him that he doesn't know anything how can WuBi believe that.and what about Duo ,is she is also doesn't know about SuYu?
Feel free to explain.