cogratulation papa-pepper. you have caught although one and a little one. We call sili fish in local name, (Mastacembelidae Eel)
including fish habitat in a river that is becoming endangered. These fish prefer to live on the banks of the river premises muddy river and under the shade of trees because it can not be exposed to direct sunlight.
So, according to my experience when I was child, you will caught the bigger one in a place that is essentially muddy and shaded by trees.
Good luck.