It's an older round, used mainly in old revolvers. It is NOT compatible with a .38 Special revolver.
It's just one of those things you've gotta watch out for when buying ammo, akin to .32 ACP/.32 S&W/.32 Long, 9mm/9mm Kurz/9mm Makarov, .22 Short/.22 Long/.22 Magnum, or .45 GAP/.45 ACP/.45 Long Colt.
The .38 S&W is an older and entirely different cartridge from the more common .38 S&W Special. The are not interchangeable. The older cartridge was originally a black powder number with shorter and fatter cartridge case, and less power than the more modern .38 Special.
If your friend is looking for +P .38 Specials these will not work.
It may not have been your friends fault. You have to be sure what you ask for is what you were given. I was in Academy a few months ago and a lady asked for 38 Special ammo. The young clerk handed her a box of 38 Super. I pointed out they were not the same and he insisted they were, only more powerful. He had to open the boxes and compare them to be convinced.