In this presentation I report on the results of the paper we published recently together with Kacper Zalewski [1]. It exploits the consequences of the observation that the hadrons, being the composite objects, cannot be produced too close to each other and thus must be correlated in space-time. One of these consequences, which we discuss here, is that the correlation function need not be larger than 1 (as is necessary if the space-time correlations are absent). Since the data from LEP [2, 3] and from LHC [4] do show that the correlation function falls below 1, the particles must be correlated and we show that our observation does explain this unexpected effect.