Convection-diffusion equations, as one of the fundamental models for describing the coupling of multiple physical fields, find wide applications across various domains. In recent years, the importance of convection-diffusion equations in problems involving vector fields such as electromagnetic fields has been increasingly recognized, leading to more complex mathematical formulations and structures of the convection terms.This talk presents an approach to the construction of the lowest order H(curl) and H(div) exponentially-fitted finite element spaces on 3D simplicial mesh for corresponding convection-diffusion problems. It is noteworthy that this method not only facilitates the construction of the functions themselves but also provides corresponding discrete fluxes simultaneously. Utilizing this approach, we successfully establish a discrete convection-diffusion complex and employ a specialized weighted interpolation to establish a bridge between the continuous complex and the discrete complex, resulting in a coherent framework. Furthermore, we demonstrate the commutativity of the framework when the convection field is locally constant, along with the exactness of the discrete convection-diffusion complex. Consequently, these types of spaces can be directly employed to devise the corresponding discrete scheme through a Petrov-Galerkin method.