Does it work if you have quotes around "High" and "Open"?
Tried that. This is one of four finds on the same script, none of the others have quotes and they all work. This is the only one dealing with two fields, though.
Do a Find for high risk then Constrain the found set to open status.
Do you get the desired results if you do a manual Find?
Meaning there are records that meet the Find requirements?
Personally, I never use this method... I use the old skool way
Enter Find Mode > Set Field > Perform Find > Omit Records etc etc
Only because you can actually follow what is happening when trying to debug...
Which is impossible using that method.
I know that doesn't help (or perhaps it does? ) just my 2c