What exactly are you trying to achieve.
show some contacts by a certain criterion
Can you please tell us you have appended a manually query parameter?
We’re asking because we have checked in the Advanced Search Filter and it’s working properly. Also the Advanced Search URL like below,
<SITE_URL>/index.php?action=index&module=Contacts&searchFormTab=advanced_search&query=true&clear_query=true
All the magic happens on this section of the query:
&module=Contacts&searchFormTab=advanced_search&query=select%20*%20from%20contacts%20where%20first_name%20=%20aaron
You need to introduce your parameters and test: