How to clean brick

My father was a mason, we had lots of brick in our home (driveway, fireplace, porch, outdoor planters, light and mailbox pilars, even a bench). I remember him talking about the "salts" coming out. He would clean the brick (but I don't remember what he used to clean it) then let it dry and apply a brick/concrete sealer. He would do this to our driveway on a hot day because it has to fully dry before he would let us step on it. Purpose was to prevent the salt and keep the brick from crumbling when it rained or with our watering. Maybe it's time for you to seal. My father used the large pump type sprayer to apply the sealer.

Maybe Oxyclean??

It's likely efflorescence and you can clean it off with muriatic acid. Sealing after cleaning will reduce its reoccurrence.

The white stains are efflorescence. Salts in the motar and brick that come to the surface from water. moisture penetration.

Efflorescence is water soluble. Cleaning it off is easy. Once clean and dry you will need to use a penetrating sealer to prevent moisture migation within the mortar.

Diluted Vinegar: If you’re in a pinch, using household diluted white vinegar can be used on efflorescence. It’s less harmful than industrial chemicals and you most likely already have vinegar in your kitchen.

Brushing: With a strong brush, you can remove efflorescence with ease.

https://www.google.com/search?q=remove+efflorescence+from+brick&source=univ&tbm=shop&tbo=u&sa=X&ved=0ahUKEwjYs9aB0I7cAhXymq0KHeouDiEQsxgIJg&biw=1536&bih=739