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We review our results in Refs.[1,2] for the masses and couplings ofheavy-light DD(BB)-like molecules and (Qq)(Qq)-like four-quark states fromrelativistic QCD Laplace sum rules (LSR) where next-to-next-to-leading order(N2LO) PT corrections in the chiral limit, next-to-leading order (NLO) SU3 PTcorrections and non-perturbative contributions up to dimension d=6-8 areincluded. The factorization properties of molecule and four-quark currents havebeen used for the estimate of the higher order PT corrections. New integratedcompact expressions of the spectral functions at leading order (LO) ofperturbative QCD and up to dimensions d< (6 - 8) non-perturbative condensatesare presented. The results are summarized in Tables 5 to 10, from which weconclude, within the errors, that the observed XZ states are good candidatesfor being 1^{++} and 0^{++} molecules or/and four-quark states, contrary to theobserved Y states which are too light compared to the predicted 1^{-\pm} and0^{-\pm} states. We find that the SU3 breakings are relatively small for themasses (< 10(resp. 3)%) for the charm (resp. bottom) channels while they arelarge (< 20%) for the couplings which decrease faster (1/m_{b}^{3/2}) than1/m_{b}^{1/2} of HQET. QCD spectral sum rules (QSSR) approach cannot clearlyseparate (within the errors) molecules from four-quark states having the samequantum numbers. Results for the BK (DK)-like molecules and (Qq)(us)-likefour-quark states from [3] are also reviewed which do not favour the moleculeor/and four-quark interpretation of the X(5568). We suggest to scan the charm(2327 ~ 2444) MeV and bottom (5173 ~ 5226) MeV regions for detecting the(unmixed)(cu)ds and (bu)ds states. We expect that future experimental data andlattice results will check our predictions.

XYZ -- spectra from QCD Laplace Sum Rules at Higher Orders