Advanced Search Customization

Hi All,

For OOTB - Advanced Search, following are high level steps:

1. User enters some words in search fields

2. OOTB processors or beans reads the field values and converts to query 

3. DB is invoked with input

4. Results are shown to UI

Now, is it possible to change the processing in step 2 as per our custom conditions ?

if so, can any one please guide us ?

Thanks