sanding dust problem

I was wetsanding a burl veneer tabletop last night, using mineral spirits and 600 grit sandpaper. I noticed this morning, after the wood had driend, that the pores are filled with white sand dust. Doesn't look very good. The veneer was previously coated with BLO. How do I get the sand dust out, considering I intend to keep up the wet sanding a few more times to get a nice sheen. The dust actually helps in filling up the pores, I just don't like the white color. Would a future application of BLO take care of this.

I know this was discussed in a thread sometime ago but I couldn't find it through search.