And even now I know, that whatsoever thing thou shalt ask of God, God will give it thee. νῦν οἶδα may be contrasted with John 11:27. In his presence she knows intuitively that nothing is impossible.
The αἰτήση is a word of more human quality than that which our Lord customarily used for his own appeals to God. He spoke of ἐρωτᾶν, to seek as an equal; παρακαλεῖν, to intercede for another; προσεύχεσθαι, to pray; δεῖσθαι, to supplicate.
It was appropriate enough that Martha should use the verb αἰτήση. Her word was a burst of excited feeling, and does not dictate to the Master what he should do. Her twofold mention of the name of God with "thou" and "thee," shows that she had not risen to highest light on the Lord's mysterious relation to the Father.
She speaks of him and to him as of a strangely gifted human Friend. But she had doubtless heard of the widow of Nain, and of Jairus's daughter, and she made no irrational suggestion. The ὅσα covers much.
Jesus loved Lazarus. He was Friend to the whole group, and known to them all.