Is the field 1 field in a related table?
find all the records where a related record has ABC in Field 1.
Then return to find mode, specify DEF in Field 1, but Constrain the found set instead of performing a find.
All of this can be done manually or via a script.
If this field is from a related table, it will find all records in the layout's table that has at least one related record with ABC in Field that also has at least one related record with DEF in Field 1.
Great - this worked! Thank you!