It would be best by far to have the name in two fields. The criteria for
FirstName would be:
Like [Enter First Name] & "*"
Similarly, for the LastName field:
Like [Enter Last Name] & "*"
With your current set-up you could try a criteria such as:
Like [Enter First Name] & "*" & [Enter LastName] & "*"
I don't think you can parse a string such as you wish to use, at least not
as a query criteria. You could probably do it in VBA code, but it would be
clumsy at best. You would need to parse the search string into two parts,
then create a SQL string that use the parts similarly to how the two
criteria are used in my second suggestion along with the rest of the
necessary fields, then use the SQL string as the recordset. In similar
fashion you may be able to create a filter string instead of a recordset
string, but in either case it is a lot of work to overcome the limitations
of an ineffective design.