Not sure 'Advanced Find' is required for this functionality (assuming you want to display all matches and don't need to implement paging).
Basically what you should do is pass the input entered by the user to the database query action, which can be 'Find', 'Advanced Find' or 'Database Query'.
If you are using 'Find', and you want to search by fields 'X' and 'Y', you should add to your 'Find' triggers 'X' and 'Y', which will get the values typed by the user. You can see an example in stage 8 of the tutorial, although in this example the trigger gets a constant value, not a value typed by the user.
'Advanced Find' is indeed more complex, because it supports specifying constraints on multiple fields, including range conditions, and it supports paging. Note that the screenshot in http://www.tersus.com/#Id=3439 does not show it, but 'Advanced Find' also has an optional trigger <Filter>, which can be used to specify additional conditions (in addition to, or instead of, most other triggers).
I hope this helps. If not, please post a follow-up question or a sample model that includes your problem.
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