This is the 7289th most frequent Portuguese word.
maiores
"Maiores" means "bigger," "greater," or "elders," depending on context.
Here, 'maiores' is used as an adjective modifying 'desafios' (challenges), indicating that these were the greatest or the most significant among challenges.
Os maiores desafios foram superados.
The greatest challenges were overcome.
In this sentence, 'maiores' is used to mean 'more detailed' or 'greater in extent,' specifying the quantity or quality of details needed.
Precisamos de maiores detalhes sobre o projeto.
We need more details about the project.
'Maiores' here refers to 'greater,' modifying 'experiências' (experiences), and conveying that the experiences in question have more significance or extent.