Is it proper to use this idiom here: "...I'm sure there is more to it than that."?
The sentence: I doubt it is a coincidence. I'm sure there is more to it than that.

Is my sentence correct and natural with the idiom: "there is more to it than that"?
If not, can you suggest a sentence with the same meaning?

Thank youI want it to mean: I don't think it is a pure coincidence. / I'm not sure it is a coincidence.

Question

Is it proper to use this idiom here: "...I'm sure there is more to it than that."?
The sentence: I doubt it is a coincidence. I'm sure there is more to it than that.

Is my sentence correct and natural with the idiom: "there is more to it than that"?
If not, can you suggest a sentence with the same meaning?

Thank youI want it to mean: I don't think it is a pure coincidence. / I'm not sure it is a coincidence.

Answer

"I doubt it is a coincidence." and "I doubt it is a pure coincidence."  are both the same in meaning. However, "I doubt it is a pure coincidence." could be that it was somewhat a coincidence, just not a 100%.

Answer

Not knowing the complete context, it seems perfect. Great job.

لا تفوّت فرصة تعلّم لغة جديدة وأنت مرتاح في منزلك. تصفّح مجموعتنا المختارة من مدرّسي اللغات ذوي الخبرة وسجّل في درسك الأول الآن!