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The fully charmed hadronic scalar molecules $\mathcal{M}_1=\eta_c \eta_c$ and$\mathcal{M}_2=\chi_{c0}\chi_{c0}$ are studied in the context of the QCD sumrule method. The masses $m$, $\widetilde{m}$ and current couplings $f$, $\widetilde{f}$ of these states are calculated using the two-point sum ruleapproach. The obtained results $m=(6264 \pm 50)~\mathrm{MeV}$ and $\widetilde{m}=(6954 \pm 50)~\mathrm{MeV}$ are employed to determine their decaychannels. It is demonstrated that the processes $\mathcal{M}_1\to J/\psi J/\psi$ and $\mathcal{M}_1\to \eta _{c}\eta _{c}$ are kinematically allowed decaymodes of $\mathcal{M}_1$. The molecule $\mathcal{M}_2$ decays to $J/\psiJ/\psi$, $J/\psi \psi^{\prime}$, $\eta _{c}\eta _{c}$, $\eta _{c}\eta_{c}(2S)$, $\eta _{c}\chi _{c1}(1P)$, and $\chi_{c0} \chi_{c0}$ mesons. Thepartial widths all of these processes are evaluated by means of the three-pointsum rule calculations, which are necessary to extract the strong couplings$g_i$ at vertices $\mathcal{M}_1J/\psi J/\psi $, $\mathcal{M }_1\eta _{c}\eta_{c}$, and others. Our estimates for the full widths of the molecules$\Gamma_{\mathcal{M}_1}=(320 \pm 72)~\mathrm{MeV}$ and $\Gamma _{\mathcal{M}_2}=(138 \pm 18)~\mathrm{MeV}$, as well as their masses are comparedwith parameters of the $X$ resonances discovered by the LHCb-ATLAS-CMSCollaborations in the di-$J/\psi$ and $J/\psi\psi^{\prime}$ invariant massdistributions. We argue that the molecule $\mathcal{M}_1$ can be considered asa real candidate to the resonance $X(6200)$. The structure $ \mathcal{M}_2$ maybe interpreted as $X(6900)$ or one of its components in combination with ascalar tetraquark.

Hadronic molecules $\eta_c \eta_c$ and $\chi_{c0}\chi_{c0}$