Yes, unlike the search utility at Ancestry.com, the search interface on AmericanAncestors isn't designed to magically home in on all of the records that might represent a specific person. But AmericanAncestors has excellent authoritative sources that aren't available on Ancestry, the search results are all good sources (no user-uploaded images of pages from an unidentifed published book, user-uploaded images of ships, etc.), and the source citations on AmericanAncestors identify the actual source of each document, rather than pretending that Ancestry.com was the author.
When I search AmericanAncestors, I typically start with the name (no other details) and see what results there are for that name. Sometimes it's an unusual name with few results, and I can easily explore the whole list of records. More often, I will select a few individual subsets of the results to review (for example, Massachusetts Vital Records 1620-1850 or the Great Migration Study Project or Jounals and Periodicals). Sometimes I add dates or places to the search form, but I don't do that if I want to see results from source types such as Journals and Periodicals, because those typically aren't indexed by the person's life dates or places.