ask for what is unattainable or impossible – British
The moon in this expression, which dates from the mid 16th century, stands for something distant and unattainable.
protest strongly about a real or imagined wrong or injustice.
Foul in this context means foul play, a violation of the rules of a game to which attention is drawn by shouting foul!
1998 - Times - She can't cry foul when subjected to fair and standard competition.
cry from the heart
a passionate and honest appeal or protest
say what your heart feels
The French equivalent cri de coeur has also been in use in English since the early 20th century.
cry over spilt milk
lament or make a fuss about a misfortune that has happened and that cannot be changed or reversed.
cry stinking fish
disparage your own efforts or products.
This expression stems from the practice of street vendors crying their wares (i.e. shouting and praising their goods) to attract customers. If a vendor were to cry stinking fish, he could not expect to attract many.
1991 - Independent on Sunday - I want to use the Home Affairs Committee Report for those in racing to go forward together and at last to stop crying stinking fish.
call for help when it is not needed
raise a false alarm
An old fable tells the tale of a shepherd boy who constantly raised false alarms with cries of Wolf, until people no longer took any notice of him. When a wolf did actually appear and attack him, his genuine cries for help were ignored and no one came to his aid.
in full cry
expressing an opinion loudly and forcefully
Full cry originated and is still used as a hunting expression referring to a pack of hounds all baying in pursuit of their quarry.
great cry and little wool = much cry and little wool
a lot of fuss with little effect
a lot of fuss about nothing
This expression comes from the idea of shearing pigs where the result could be expected to be great cry and little wool.
for crying out loud
used to express your irritation or impatience – informal
expression used to say something about your disappointment
1941 - Rebecca West - Black Lamb and Grey Falcon - For crying out loud, why did you do it?