I found the 吸鼻器 that is very good and comfortable to BB. the name is "KOUYAMI nose cleaning sucker". Price is ~$45 or 48 brought from Jusco.
I used this when my bb was at 2 months. He knows to open his nose to let me suck his 鼻水. cos he feel comfortable after removing it.
Just try it, its very useful esp. bb can sleep well at night.