I have made a formAction for this. But the problem is, for single word answers it is guessing wrong intent like greet or goodbye. How to force nlu to look for specific intent if the entity is not captured in first intent. Even after forcing, how to train nlu for capturing entities from those single word answers.
If your entities will come from a fixed set of values, then use lookup tables, as Juste has recommended. If your entities can have totally random values and they will overlap with other entities, then use the approach described here.