What's their Name? genealogical searching

A few days ago I was looking for a woman named Barthena/Barthona Carter in AR in the federal census (although on one census she was listed as Parthena).  I could not find her anywhere in AR.  I checked across the border in south western MO, Barry Co., where one of her adult sons was living.  I was using Ancestry's census site and therefore indexes.  Nothing, so I started reading every name on the multipage index.  Finally, I found a family with the head of household named Carter Barthany.  And there were the children, all with the last name of Barthany.