Does using Induction in scientific experiments make knowledge for us?

Our presumption for induction reasoning is the Principle of Causality. this Principle asserts that there is a connection between the cause and phenomenon. if we know the cause we can predict the raised phenomenon but in real situation especially in scientific experiments it is very hard to trace the causes and we just rely on the happened phenomenon and in most of cases the cause(s) will be remained unknown to us. if we know the cause (by other means rather than experiments) our instance of knowledge (the result of induction ) will be justified so because of lack of knowing cause in induction reasoning our true belief can not be get justified.