This is very interesting as I remember a relative of mine saying they do this and have the same issue. But I wasn't aware this was a thing as I never read like that. Maybe you could try to move your eyes swiftly from the beginning of a line to its end (while trying to retain as much information as possible)? Doing this over and over might increase your reading speed little by little. If you focus too much on little details often I feel that eats away at your reading speed.