dogbone - porous brick and water infiltration
It is normal for water to pass through veneer brick and run down the back side of the brick to horizontal flashing where the water is forced to weep outward.
Some brick allows more water to pass. Some cavities are not detailed properly and can allow water to enter the backup system.
If you are only finding water at a basement door I would first assume that the flashing and weeps at the head of the door are not properly installed. The next assumption I would make is that the threshold of the door is not properly designed.
If you want to take the extreme step of sealing the brick I recommend hiring a waterproofing specialist; it is definitely not a do-it-yourself task.