Depending on the context, it can be translated in many different ways. Below are some of its possible translations .
"He/she should think more, shouldn't he/she? "( the speaker thinks that he / she should think more)
"I should think more, shouldn't I?"
"You want me to think more, don't you?"
One again, how to translate the phrase Depends on the context, so please see the three translations above as an example.
I hope this helps even just a little bit.