Discussion limitations of a study

I am writing a manuscript about a cohort study. I have not detect any statistical difference in some parameters in t-student but the number of patients studied are suboptimal.
In the discussion, I would like to emphasize "our findings should not be interpreted as a lack of differences, but rather an inability to detect these differences"
Do you know whether this assumption should be written in the study? Do you propose any other sentences?
I would appreciate some example from another study.
Thank you very much in advance.