A key objective of developing natural sciences consists in heightening the information content of conclusions regarding phenomena in surrounding world. However, the progress of theoretical physics in XX-th century has not complied with this objective, which evidences the plasma studies. Namely, traditional conceptions of plasma theory cannot provide appropriate level of reliability of final predictions. This book clarifies the reasons of non-informativeness of plasma theoretical deductions: the asymptotic convergence of iterative approximations to the plasma model and the substitution of real plasmas by plasma ensembles (the ensemble method). The book introduces basic principles of developing informative plasma kinetic scenarios. The book exposes also a high-informative correlation analysis of plasma kinetics that adopts these principles to reducing of full description of a weakly turbulent collisionless plasma to its high-informative kinetic analog. Basic nonlinear phenomena in plasmas with Langmuir turbulence are reconsidered. The book is oriented on scientists and students willing to master in developing high-informative models of phenomena in plasmas and other objects.