To be insatiably greedy; to be discontented with what one has and always want more; to have one's cake and eat it too.
他总是吃着碗里瞧着锅里，对现在的工作总是不满意，老想着跳槽到更好的公司。
He is always discontented, never satisfied with his current job and always thinking about switching to a better company.
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