...the boys were sitting around in the Palace sipping the result of Eddie’s latest contribution. Gay was there too, the latest member of the group. Eddie sipped speculatively from his glass and smacked his lips. “It’s funny how you get a run,” he said. “Take last night. There was at least ten guys ordered Manhattans. Sometimes maybe you don’t get two calls for a Manhattan in a month. It’s the grenadine gives the stuff that taste.”
John Steinbeck. Cannery Row.
What does it mean "It’s funny how you get a run"?
I think I understand all words but do not understand whole sentence.
Is it possible to say the same in other words and more simply?