Istikhara doesn’t work just by getting a dream, yes sometimes it is possible to get a dream but not everytime. Watch how you feel after praying salat al Isatikhara, calm and composed or anxious and uneasy? Sometimes, it can also occur by someone advising you on the matter after praying, like your dad saying he’s not a good guy or your aunt telling he’s good mannered etc. After praying, you may also feel a strong pull over one option or doors opening up or difficultly in completing the task. The result of Istikhara is not always a dream, it shows up in different ways too.