If you are trying the find the origins of an immigrant ancestor, don’t be afraid to jump the pond and start research in the place of origin if you get stuck.
Researching the person in the place you know they lived (after immigration) is a good strategy to start your research into an immigrant ancestor. That may give you clues about their place of origin, their relatives, and their social network. But sometimes, even the most detailed research in a place of destination does not reveal information about the place of origin.
If you know the immigrant came from the Netherlands, don’t be afraid to jump the pond and do some searches in Dutch websites, for example in one of the top 10 websites for Dutch genealogy. See How to find my immigrant ancestor in the Netherlands for more strategies.