I am fairly positive you can get any enchantment on a book. There is a website called minecraftenchantmentcalculator.com and you can use it to figure out what level is best to enchant at for specific enchanments on specific items.
According to that website, you should try enchanting book at level 18 for the greatest chance of getting sharpness 2. It says enchanting books at level 18 gives you an 11.5% chance of getting sharpness 2.
If you use that website make sure to change it from "Minecraft 1.7" to "Minecraft 1.46 to 1.6" since it seems you are doing this on an Xbox.
According to that website, you should try enchanting book at level 18 for the greatest chance of getting sharpness 2. It says enchanting books at level 18 gives you an 11.5% chance of getting sharpness 2.
If you use that website make sure to change it from "Minecraft 1.7" to "Minecraft 1.46 to 1.6" since it seems you are doing this on an Xbox.
Stay fluffy~