Problem with filter condition in trigger and which not diaply on broker & not working

Hi Guys,
We have an error in server logs, like “No condition matches to specific document in the trigger”. We verified the publishable document fields and content types, we have one field with content type is ISO latten characters. When we create a filter condition on that particular field, at runtime, server throws above error message.

We created a filter conditions are like, %fieldName% L_EQUALS ‘X’, %fieldName% L_EQUALS “X” and vice versa. Even though the condition is not displayed in the broker level and not working out?
Is it possible to create filter condition with this type of content fields? If ok, please let us know the filter condition structure.
If possible please advice, what type of content fields we create the filter condition in trigger?
In case of special character in the publishable document, Please advise how to create the filter condition on those fields?
Thanks and Regards,