You can't find all characters in Sinhala Hodiya either!
The beauty of Sinhala and similar languages is that we can create thousands of characters using only a few basic characters and modifiers.
Sinhala Unicode Codepage includes sufficient basic characters to build all possible Sinhala characters.
For example, we get "ku" with the sequence "ka" and "papilla".
Since both "ka" and "papilla" are there in the Codepage, a seperate "ku" is not necessary.
In old printing machines, it was necessary to have a large matrix of thousands of characters. With modern computers, this need has gone away, because they can be programmed to create all those characters using only the basic set.