Have you taken the new Seminar on SQL [http://www.599cd.com/site/courselist/seminars/access-sql/]
It's excellent! I'd advise it very much as it will help with your question.

So lets first break down the SQL Statement:-

SELECT

PROIDNO, PROCLIDNO, PROCLNAME, PROPADDR1, PROPADDR2, PROPSTATE, PROPZIP, PROIT2, PROUD22, PROUD23, PROUD24, *

Are there more than 11 fields in that table?

The * means select all the fields from the table, but you have selected some fields before this, are both necessary?

FROM STKLKP
This is the name of the table you are getting the data from.


WHERE (((STKLKP.PROIDNO) Like IIf(IsNull([Forms]![fdlgSelect]![Number]),"*",[Forms]![fdlgSelect]![Number])) AND ((STKLKP.PROCLNAME) Like IIf(IsNull([Forms]![fdlgSelect]![Client]),"*",[Forms]![fdlgSelect]![Client])) AND ((STKLKP.PROPADDR1) Like IIf(IsNull([Forms]![fdlgSelect]![Street]),"*",[Forms]![fdlgSelect]![Street])) AND ((STKLKP.PROIT2) Like IIf(IsNull([Forms]![fdlgSelect]![Description]),"*",[Forms]![fdlgSelect]![Description])) AND ((STKLKP.PROPCITY) Like IIf(IsNull([Forms]![fdlgSelect]![City]),"*",[Forms]![fdlgSelect]![City])));

In the WHERE statement you have multiple Immediate IF functions,

an example is
  iif ([Qty] > 10, "large", "small")
which is another way or writing
  If [Qty] > 10 Then
      result = "large"
  Else
      result = "small"
  End If

So I guess you have textboxes on your form [fdlgSelect] named [Number, Client, ...]
These relate to the field names in the table you are searching

  PROIDNO -> Number, PROCLNAME -> Client, PROPADDR1 -> Street, PROIT2 -> Description, PROPCITY -> City

The WHERE is filtering through your records and if there is no value in that textbox (IsNull(Forms]![fdlgSelect]![Number])) then show all (*) else search for that value the user has entered (Forms]![fdlgSelect]![Number])

  IsNull(Forms]![FORMNAME]![FIELDNAME])

This does the same for the rest of the textboxes Client, Street etc.
It has the LIKE keyword which when joined with the *
"* allows you to match any string of any length (including zero length)"
But if not it will only match EXACTLY what the user entered.

You are joining the WHERE criteria with ANDs when you might want ORs as everything must match for that one record.

Richard answered a similar question in the forum
[http://www.599cd.com/blog/display-article.asp?ID=352&Thread=Search+++Lookup+++Display&ExpandAll=YES]

Here he advises that a comma seperated list isn't the best option.

There is a Search Seminar coming out very soon, which will be using the SQL seminars so I'd advise looking out for that after getting the SQL.

Regards
Alex