Did you ever come across the problem of SQL criterion not getting fired while dealing with Search Select Advance filed in CRM?
If yes, then here is what you must have a look at:
1. Check whether the SSA field has been customized in ASP pages or on Create Script then check with SQL condition set for the same.
2. If the length of SearchSQL exceeds some limit, the condition does not get fired. The limit of length is varying by CRM version. So you must consider the length of the SQL query while writing SearchSQL.