1
general::
Phrase(s): more (to something) than meets the eye
Fig. [there are] hidden values or facts regarding something. • There is more to that problem than meets the eye. • What makes you think that there is more than meets the eye?
McGrawhill's American Idioms And Phrasal Verbs
2
general::
A hidden significance, greater than is first apparent, as in This agreement involves more than meets the eye. [Mid-1800s]
American Heritage Idioms