English Standard Version (ESV)
Imagine a young kid who doesn't realize what an ice cream truck is. He walks up, knowing nothing about what is inside, and has the wisdom to ask only for a glass of water, thereby not receiving any of the deliciousness inside, because his experience can't grasp the wonders of a truck full of ice cream.
This is what this story is like -- Jesus Christ, God incarnate, the Savior of the world, is standing before this woman, offering her the gift of eternal life, but her mind and experience cannot grasp what he is offering. Her experiences blind her to who and what is before her, and so she is only able to ask for water to quench her physical thirst.
When we come to Christ, we must open ourselves up to the work of the Holy Spirit, so that we can set aside our preconceived notions of what God can do for us -- because God is seeking to do more for us than we can ask or imagine. God's vision is so much bigger than our own, but we need to submit to his Lordship and humble ourselves, so that the riches and fullness of God's grace might wash over us and transform every part of our lives.