Good morning @Former-Member ..... 😊

It's a bit hard to tell from the photo whether this is acrylic or oil paint.

If the white spots are only in the background and not across the flowers or vase at all, then Iwould imagine they are an effect that the artist intended.  If you don't like them, you can touch them up, but be careful.  You are probably better to discolour them slightly, so they are off-white, rather than try to match any other colour from the background.  You would need to be very skilled to do that.

Acrylic is used with water, but it is also very quick-drying.  It would mean you could buy a tube of off-white acrylic from an art supply shop (somewhere with a big range of colours) and be able to water it down, apply it to a few spots, and if you don't like it, quickly dab it back off afghani with a tupissue before it has the chance to dry properly.

I would advise taking the painting in with you and asking the advice of the staff art the shop.  Mostly they are trained and practicing artists, giving them the ability to advise customers regarding the materials they sell.

I hope that helps you @Former-Member ....

🎨💕