Solid Wooden Floors - Cleaning

We recently had solid wooden floor in our dinning room - Solid Oak stained a dark coffee . Delighted with the end result apart from one small problem it is impossible to keep clean. The room has a set of french doors our on to the garden and if anyone steps on them after been outside they need to be cleaned again.

Can anyone recommend a way of cleaning this floor.
What do you use? Any help appreciated.
Thanks

We use a spray-on wood polish most of the time and wipe it with a dry mop. For a really deep clean you have to get down on the hands and knees to do it though.