Novel results in perturbation theory for LSS

Major improvements in the theoretical understanding of LSS have been possible due to the effective field theory approach. In the first part of this talk, I will discuss how to go beyond the one-loop calculation, presenting novel two-loop results and their information content. I will also show how to extract information from higher-loop orders using renormalization group equations. In the second part of the talk, I will discuss how multi-tracing nonlinear theory can be used to extract additional information from galaxy clustering.