As printer technology advances, more and more of these colours can be printed as more inks are introduced. Some printers now have red, green and blue inks as well as the more standard cyan, magenta, yellow and black inks, because they can then print more of the brighter colours - the extra inks extend the gamut of the printer which means more colours can be printed.

The dark colours of the printer can also be a problem. you might notice that your printer with a standard profile does not print all the detail in the shadows of an image compared to what you can see on the monitor.