The emergence of cloud manufacturing (CMfg) provides a new opportunity for the change of manufacturing towards service-oriented model. Cloud service composition (CSC), which can realize the added value of cloud service (CS), is the core to implement CMfg. Since there always exist correlations among CSs, especially composable correlation (CoC), which can affect the construction of CSC path. Hence, how to mine the CoC among CSs and judge which kind of CoC between them is a key issue. This paper presents the formalized description for CoC, and designs decision algorithms to judge CoCs between CSs based on bipartite graph. The case study illustrates the application of proposed algorithms.