Domain testing, a technique for testing software or portions of software dominated by numerical processing, is intended to detect domain errors that usually arise from incorrect implementations of designed domains. This paper describes our on-going work aiming to provide support for revealing domain errors using formal specifications. In our approach, formal specifications serve as a means for domain modeling. We describe a strong domain testing strategy that guide testers to select a set of test points so that the potential domain errors can be effectively detected, and apply our approach in two case studies for test cases generation.