The femtoscopic technique has emerged as an invaluable tool in probing the strong interactions between pairs of stable and unstable particles. This presentation stresses that it can contribute uniquely to understanding the many candidates of exotic hadrons discovered since 2003. The essential idea is to check the molecular picture for these exotic hadrons by extracting the strong interactions between their constituents. We show first how the general features of the strong interactions manifest themselves in the femtoscopic correlation functions and then we demonstrate the proposed strategy by taking the $D_{s0}^*(2317)$, the pentaquark states, $P_c(4457)$ and $P_c(4440)$, and the tetraquark states $Z_c(3900)$ and $Z_{cs}(3985)$ as concrete examples.