The calculated rovibrational energy levels and infrared spectra for OCS-(pH(2))(2), OCS-(oD(2))(2), OCS-(HD)(2) and mixed OCS-pH(2)-He trimers are obtained by performing the exact basis-set calculations for the first time based on the newly developed potential energy surfaces (J. Chem. Phys. 2017, 147, 044313). The "adiabatic-hindered-rotor" (AHR) method is used for reduced-dimension treatment of the hydrogen rotation. The predicted band origin shifts and the infrared spectra are in good agreement with the available experimental values: for the band origin shifts and infrared transitions, the root-mean-square(rms) deviations are smaller than 0.044 and 0.002 cm(-1), respectively. We extend the assignments to the unrecorded infrared transitions for OCS-(pH(2))(2) and OCS-(HD)(2) complexes and identify the infrared spectra for OCS-(oD(2))(2) and OCS-pH(2)-He for the first time. Three-dimensional density distributions for the ground states of OCS-(pH(2))(2), OCS-pH(2)-He, and OCS(He)(2) show that the pH(2) molecules are localized in their corresponding global minimum regions, while the pronounced locations of the He atoms are missing in OCS-pH(2)-He and OCS-(He)(2) with forming incomplete circles around the OCS axis. A clear tunneling splitting is observed for the torsional motion of the two hydrogen molecules (pH, HD, or oD(2)) on a ring about the OCS molecular axis, whereas no tunneling splitting is found in OCS-pH(2)-He or OCS-(He)(2) due to a much lower torsional barrier.