'Secret' in the Bible

Also in thy skirts is found the blood of the souls of the poor innocents: I have not found it by secret search, but upon all these.

But if ye will not hear it, my soul shall weep in secret places for your pride; and mine eye shall weep sore, and run down with tears, because the LORD'S flock is carried away captive.

Can any hide himself in secret places that I shall not see him? saith the LORD. Do not I fill heaven and earth? saith the LORD.

But I have made Esau bare, I have uncovered his secret places, and he shall not be able to hide himself: his seed is spoiled, and his brethren, and his neighbours, and he is not.