Molecular detections via cross-correlation analysis. The CCF of selected molecules for TWA 27A and TWA 28, are computed between model residuals (with and without each species) and template spectra over radial velocities up to 2000 km s⁻¹. S/N ratios are calculated by normalising the CCF peak to the standard deviation of the CCF-ACF difference (secondary panels). ACF is the autocorrelation function of each molecule.