农夫山泉甜个屁
[nóng fū shān quán tián gè pì]
In original marketing terms, Nongfu Spring is a well-known Chinese bottled water brand emphasizing natural sweetness from the source. Here, however, this user seems quite ironic saying 'Farmers Mountain Spring, sweeter my ass', which may show his disdain towards exaggerating advertisements, or any overblown promises that proved to be untrue.