There are some expressions that are consists of couple of words which are referring a single word [an object,a person or a place]. We call this way of indirect naming as ´Dolaylama´

"yavru vatan":  Kıbrıs

"Büyük  kurtarıcı":  Atatürk
"Ulu  önder":          Atatürk

"derya kuzuları": Balık

"File bekçisi": Kaleci

" Meşin Yuvarlak´ : Futbol Topu

"Türkiye´nin kalbi": Ankara

Thank you for bringing forward this important stylistic issue, tunci. The use of customary metaphors often makes sentences very difficult to understand for a learner. Is there a dictionary of Turkish metaphors somewhere?

Do good authors use these old metaphors a lot? I guess in some languages their usage is not recommended while in others they have a certain prestige. How is it in Turkish?

Metaphors have a lifespan. They are born, they live and they are forgotten. Some metaphors become extremely popular and fashionable but don´t live long. Some have always been there so that we hardly notice them. (No wonder, a word itself is a metaphor.) Mother tongue teachers in my country strictly warn students from using both very customary and very fashionable metaphors. If one can´t use fresh metaphors he should better abstain from using them. But I have a feeling there are cultures where mastering old metaphors is a sign of civilization.

http://www.ottomansouvenir.com/Turkish_Proverbs/Turkish_Proverbs_4.htm

Nice link, gokuyum. I have noticed Turks love their proverbs.

I found something else:

                              http://tdkterim.gov.tr/atasoz/

You can search for idioms and proverbs looking for the index word either from the dictionary entry or the explanation. Quite funny reading. Try some frequent words and you will get plenty of interesting results.