It's NOT the wood you're trying to clean; it's the polyurethane you're trying to clean!
You can do one of 2 or 3 things. 1) If you put on the urethane finish on, read the can for what to use to clean it with. 2) If #1 is true but there are are no suggestions for cleaning the urethane, then call the manufacturer of the urethane. 3) If the wood was pre-finished, you must contact the retailer, preferably the manufacturer, for cleaning instructions. Doing the wrong thing, in the least, will void the warranty! At the worst, using the wrong cleaning agent will ruin your floor.