This is the 3432nd most frequent Russian word.
приезжали
"Приезжали" means "came" or "arrived" (past tense, plural).
The word 'приезжали' is used here to indicate a completed action in the past where the subject 'мы' traveled to a location, Moscow.
Мы приезжали в Москву на прошлой неделе.
We visited Moscow last week.
The word 'приезжали' is utilized in a question to ask about the time of the last occurrence of someone's arrival.
Когда вы приезжали сюда в последний раз?
When did you come here the last time?
The word 'приезжали' is used to describe a repeated past action, specifically the frequent arrivals to visit their grandmother.