This is the 4160th most frequent Portuguese word.
sia
"Sia" is not a standard Portuguese word. It may be a typo or a non-standard term without meaning in this context.
Here 'seja' is a subjunctive form of 'ser', indicating a condition or possibility.
Ela sempre responde 'sim' à pergunta que seja positiva.
She always answers 'yes' to a question that is positive.
In this sentence, 'seja' expresses a wish or hope in the subjunctive tense for 'ser'.
Espero que seu resultado seja excelente.
I hope that your result is excellent.
Here 'seja' is used to denote allowance and acceptance, again in the subjunctive mood of 'ser'.