OsclassWizards- modifying the search box

[fumi]

Could someone tell me how to modify the search box on the top page and the search result page?
To be more specific..
<Top page>
I would like to...
-Remove search by keyword (I'm making a site in Japanese and that's probably why, but this function is inconsistent and not very useful)
-Remove search by category
-Keep search by locations
-Add search by dates (I have added the date intervals from "Custom fields")
 
<Search result page>
I would like to...
-Remove search by keywords
-Keep search by locations
-Remove search only ads with pictures
-Keep search by price
-Add search by dates (I was able to do this when I added dates from "Custom fields")

Thank you very much in advance!

[Shafi]

Which theme are you using. ?

[fumi]

I'm using the OsclassWizards.