krita-1.4.2 on amd64 (build from app-office/krita) does not have its documentation available through the handbook. I don't know if the krita's documentation is installed at all, to be honest.
It would not be a major problem is the program was not so damn complicated to understand and if www.koffice.org was not down today... :(
Press F1 (Krita Handbook)
The handbook starts but says:
The requested help file could not be found. Check that you have installed the documentation.
I have of course the 'doc' flag on and I have apparently all the other KDE handbooks available.
The release doesn't include documentation for Krita. 1.5 will have some, though.