Meanings of reveals certain in английском

The outline of the message given here reveals certain main features:

A study of that boyhood reveals certain characteristics which reappear constantly in the poet's work.

The fortified bedroom in the house by the Kafue River, surrounded by large dogs, reveals certain conditions.

Mr. Whistler's portrait reveals certain general observations of life; but has he given one single touch intimately characteristic of his model?

I think it is a very forensic analysis of a British legal process and I think it reveals certain things that... don't add up.

The spiritual cause is sometimes referable to God, Who reveals certain things to men in their dreams by the ministry of the angels, according Num.