"系统论方法" can be translated into English as "systematic approach" or, more specifically in the context of systems theory, "systems theory approach" or "systems approach".
"Systematic approach" is a more general term that emphasizes a methodical, organized, and comprehensive way of dealing with problems or analyzing situations.
"Systems theory approach" or "Systems approach" specifically refers to the application of systems theory principles and methodologies to understand, analyze, and solve complex problems by considering the interrelationships and interactions among the components of a system.
In academic or professional contexts, especially when discussing complex systems or interdisciplinary fields, "systems approach" or "systems theory approach" would be more precise.