«زَي غِيطِ الْكُرُنْبْ كُلُّهْ رُوسْ»

The picture is a cabbage plot once the crop has been cut. What stays behind in the soil are the leftover bits of the heads, not whole, marketable cabbages: scraps no one gathers that serve no purpose. It suggests waste, not plenty.

Used figuratively, the comparison targets something of poor quality, where the greater part offers nothing of value and the bulk of it is of no use to anyone.

Use it for a thing, collection, or result judged poor overall, where most of what is present brings no benefit. It belongs to informal everyday speech and works as a critical comparison introduced with 'like'.