Is Winnie right in being hopeful that her dad will come and find her and he is probably out searching for her that very minute?Why?

Yes, Winnie is right. Her father has had people searching for her all day.

Winnie's head whirled. Remembering the man in the yellow suit was the only thing that kept her from weeping. "He's told them by now," she thought, rehearsing it. "They've been looking for me for hours. But they don't know where to look! No. The man saw which way we were headed. Papa will find me. They're out looking for me right now."