Use Advanced Search under Query. If the field is a text field (including date fields) one of the choices in the Condition box is "is empty", which naturally grays out the value field. If it is a checked field, one of the choices is "is not checked". Of course, for a check box, "not checked" may be what you want anyway.

[quote=hardbop-man]I want to search for fields/checkboxes that are empty so that I know where to put my spare time