To scratch one's throat
Scratching the throat and changing the voice, a Chinese idiom, Pinyin is n á oh ó Uli è s ǎ ng, which means breaking the tune and out of tune. It comes from the second edition of Guangling moon by Tingna of Mingjiang.
The origin of Idioms
Jiang Tingna's Guangling moon of Ming Dynasty is the second one: "if you want to have a new voice, you should avoid scratching your throat."
Idiom usage
As an object; out of tune
To scratch one's throat
make a fetish of somebody or something - fèng rú shén míng
the man who rather trusted his measurements than placing any confidence in his own feet when buying shoes - zhèng rén shí lǚ
all over the mountains and plains - mǎn shān biàn yě