This is the 881st most frequent Italian word.
vostra
"Vostra" means "your" (feminine singular, formal or plural).
The word 'vostra' is used here as a possessive adjective referring to 'your' (plural possessive form) indicating ownership by the addressed group.
Qual è la vostra opinione su questo argomento?
What is your opinion on this topic?
In this sentence, 'vostre' is a possessive adjective in the plural feminine form corresponding with 'keys', showing possession for a group being addressed.
Le vostre chiavi sono sul tavolo.
Your keys are on the table.
Here, 'vostra' is a possessive adjective describing the noun 'capacità' (skills), indicating that the skill belongs to the addressed entity.