If you're having difficulty finding people in databases that you expected to be there, it can be due to a number of things, and there are various search strategies you could try to find entries:

• Search with wildcards (i.e. for Alexander try searching for Alex* ) to bring back likely misspellings etc.
• Try clicking on the surname variant option box. This then searches for similar sounding names, e.g. Bayley, Baily, Bailey, Baylee, etc.