Answer:
Ellos no saben la poesía de Gabriela Mistral.
Ellos no conocen la poesía de Gabriela Mistral.
Step-by-step explanation:
As shown above, there are two ways of completing this sentence.
"Ellos no saben la poesía de Gabriela Mistral" states that they do not know of the piece or poetry of Gabriela Mistral.
"Ellos no conocen la poesía de Gabriela Mistral." states that they do not know the piece of poetry of Gabriela Mistral.
The two words, saber and conocer, have the same meaning in English which is "know". But they could have a impact depending on the context of the sentence they are used for.
For instance, "Ella no sabe sobre la poesia de Gabriela Mistral", which means, "She doesn't know about the poetry of Gabriela Mistral". The verb conocer could not be used in this sentence because it would not make sense.
Hope this helped - Maria