This is the 684th most frequent Finnish word.
useamman
"Useamman" means "several" or "more than one" in English.
Here, 'useamman' is in the partitive case indicating more than one year, emphasizing duration or accumulation.
Hänellä on useamman vuoden kokemus alalta.
She has several years of experience in the field.
In this instance, 'useamman' is in the partitive case, modifying 'books' to denote a quantity greater than one but not fixed.
Valitsin useamman kirjan, jotka vaikuttivat mielenkiintoisilta.
I chose several books that seemed interesting.
Here, 'useamman' modifies 'persons' in partitive plural, indicating opinions from more than one individual.