A branch on a vine draws its sustenance from the vine. Apart from it, it withers and dies; it bears no fruit. Jesus is likened as the true vine, God the Father is the gardener, and we who make up the Christian Church are the branches; our lives being our fruit.
If we remain in the vine and Christ Jesus' words remain in us, we can ask whatever we wish of God, and it will be given to us. It is to God's glory that we bear much fruit, showing ourselves to be His (Christ Jesus') disciples. 1
1 (John 15:1-1-8)