What affects the amount of delivery jobs you get?

I only see 1 or 2 delivery jobs, sometimes none until I refresh four times (I don't have Wuling node, just the other three) What determines the amount you get? Or am I being unlucky? It's the same for me at different times of the day I heard the number of friends doesn't matter because you get it from random players (I have 90 friends, and all have been online for less than 20 hours)