In order to identify information in your composition that may contradict your thesis, you should

you should try to re analyze what you wrote in your thesis if this is like an argumentative essay or explanatory; information that might take the opposite side of what you're trying to explain can take down the whole essay since as you say it's a thesis which is the main sentence of what you'll be explaining So a few tips should be

1)Check twice before concluding what you'll debating,concluding,explaining

2)Be able to have strong, reliable sources

3)Explain (to yourself) why you included those particular reasons,topics, or selected points (that will be in your supportive paragraphs) if you cant explain the reasons you will know they might be either weak or contradictory for your topic.