Multiple options for query criteria

[graccess]

I have a form with three combo boxes that I want to use for sorting my data. The user has the option of filing in anyone of the three boxes, I plan on disabling the other two boxes if one has already been selected. Since the combo box category will vary, I wanted to have in my query a criteria expression in each of those respective fields. When I run the query with just one criteria expression I receive my results but when I add in the additional criteria I naturally receive nothing. Whats the solution here? thanks again!

[Xipooo]

In your criteria you can use "[Form]![FieldName] OR [Form]!FieldName] Is Null"

That will search for what you typed in that field or if if it's null it will basically ignore it as criteria.

[graccess]

In your criteria you can use "[Form]![FieldName] OR [Form]!FieldName] Is Null"

That will search for what you typed in that field or if if it's null it will basically ignore it as criteria.

Similar to the process I used, it returns data when I apply the expression to one criteria, but when I enter this code in each of the three criteria fields of my query at once, I get nothing back. Any way you know to combine this in a query or am I better off using VBA code in a click event that launches a report with the filtered information?