[en] A statistical theory of strong plasma turbulence in nonlinear-nonequilibrium state is extended. By use of the spectral decomposition method, the renormalized propagator is decomposed into the projection operators. The decomposition of fluctuation fields into the least stable branch and other branches is explicitly made. The extended fluctuation dissipation theorem is derived for each decomposed renormalized mode. The decorrelation rate, eddy damping rate, fluctuation level and correlation functions are obtained even in the case that the cross-correlation functions and auto-correlation functions are of the same order of magnitude. The Fokker-Planck equation is reformulated for fluctuation components of each branch. These results are generalization of the previous result. It is confirmed that the solutions, probability distribution function and related transition probability which have been obtained in previous analyses are found valid apart from a numerical coefficient of the order of unity. In order to show the wider applicability, a case of plasma turbulence which is described by the four-field reduced set of equations is also discussed. (author)