A critical idiom for a deceitful person or politician who promises grand unrealistic visions to gain influence.
dream peddler / purveyor of false hopes / illusion spinner
msee wa story za jaba / tapeli wa hope
"Usimwamini mchuuzi wa ndoto anayeahidi utajiri wa haraka bila kazi."
Translation: Do not trust a dream peddler who promises quick riches without work.