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In the QCD sum rules for the tetraquark (molecular) states, the higherdimensional vacuum condensates play an important role in extracting thetetraquark masses. We carry out the operator product expansion up to the vacuumcondensates of dimension-10 and observe that the vacuum condensates ofdimensions $6$, $8$ and $10$ have the same expressions but opposite signs forthe $C\gamma_5\otimes \gamma_\mu C$-type and $C\otimes \gamma_\mu C$ typefour-quark currents, which make their influences distinguishable, and they areexcellent channels to examine the vacuum saturation approximation. We introducea parameter $\kappa$ to parameterize the derivation from the vacuum saturationor factorization approximation, and choose two sets parameters to examine theinfluences on the predicted tetraquark masses, which can be confronted to theexperimental data in the future. In all the channels, smaller value of the$\kappa$ leads to better convergent behavior in the operator product expansion,which favors the vacuum saturation approximation.

Does vacuum saturation work for the higher dimensional vacuum condensates in the QCD sum rules?