Neo4j node api don't know how to find/get node by parameters not only id

i'm new to neo4j, i'm reading the documentation and a sample, small app based on the node module (neo4j), but i don't see a way to get a node or nodes based on parameter/r.

something like:

var node = db.find({user: "WillSmith@iam.com", password: "5@^632g23^@#23"});

Can anyone explane it to me, or point me to a good resource explaining it :)