This is the 684th most frequent Portuguese word.
sua
"Your" or "her/his/their" (possessive pronoun).
Here, 'sua' is the possessive pronoun used for referring to 'your' in a formal or third-person context, describing possession of the ability.
Sua habilidade para resolver problemas é incrível.
Your ability to solve problems is incredible.
In this case, 'sua' serves to indicate possession, meaning 'her,' referring to something belonging to the mentioned third-person 'Ela' (she).
Ela trouxe sua mochila para a aula hoje.
She brought her backpack to class today.
Here, 'sua' represents 'your' as a possessive form, directing the imperative sentence to the addressed person.