Can I do complex file search?

Hello,

In Bridge (presently working with both CS3 and CS4), I nned to elaborate complex file search and create smart collections using complex search queries such as:

[file type is JPEG] AND ([a metadata contains "XXXXX"] OR [a metadata contains "YYYYY"])

or even more complex:

[file type is JPEG] AND ([a metadata contains "XXXXX"] OR [a metadata contains "YYYYY"]) AND ([width > nnnn] OR [height > pppp])

Is this possible? How?

Thanks in advance for any help or suggestion