{not} [have] a good word to say (for|about) {sth}

to have a very negative opinion about someone or something and to be unable to say anything positive or complimentary about them

The disappointed customer returned the product, saying they had not a good word to say for it, and demanded a full refund.
The art critic's scathing review left the artist feeling devastated, as they had no good words to say about her work.
The food critic was so unimpressed with the restaurant's cuisine that he had not a good word to say about it, giving it a one-star rating.
The movie reviewer was so bored by the film that he didn't have a good word to say for it, calling it a waste of time and money.
He doesn’t have a good word to say about his old job; he always complains about it.