In order to make a full-dimensional accurate PES of a molecular system, three components are needed to be taken into account: data quality, data sampling, and data fitting, indicating that the data locates at the core position. Indeed, data and artificial intelligence become an important pillar of an integrated strategy for studying complicated phenomena. The data here refer to a set of configuration points and their associated electronic energies. These configurations are not only far from equilibrium, but also located in several regions of different stationary points, including reactants, products, transition states, and intermediates. The complicated electronic structure makes it difficult to get a high-quality dataset. Various issues have been discussed and reviewed for electronic structure calculations. Some useful tips and suggestions are given to obtain accurate and well-behaved energies without discontinuities and noises.