I want to create an If-else condition for entity003, if user’s response for entity003 is yes or similar to yes (like yes please, Yes I am,…) Then go to message002. How can I do that? Is it possible with contain operator in drop down menu?
Andrea,
You don’t say what type of entity Entity0003 is.
I am guessing from your comments that you’ve set it as a String. If so then this is not what you want to use here. (String is rarely the correct type 
)
Instead you should use a List of Items entity (enumerated version). This entity is a essentially a mapping from something in the user’s utterance - the synonyms, to a value. The connections will be testing that mapped “value”. So in actuality this connections panel need not look any different.
The other alternative is to use a confirmation node which is specifically set up to handle yes or no style prompts, and it deals with all of the possible variations. The challenge with yes/no is that there are many different ways of saying that and it can be tricky to get the training correct for a List of Items entity.