In this case, you cannot have your cake and eat it too...
You say that you want to "remove/disable the searches from appearing" but you "don't want to delete [your] search history." Personally, I cannot see what use the search history is to you if it doesn't appear when you begin searching on a term. There is no other way to access search history, except by examining the .dat file where those searches are retained.
If on the other hand, you mean that you don't want to delete your BROWSING history, then what you want can be accomplished.
To remove previous searches:
- Press 'delete' key after scrolling to search term using arrow keys
To remove all previous searches:
- Open the file 'search_field_history.dat' from opera:config#Opera%20Directory with Notepad (or any ANSI editor)
- Delete the files entire contents and save
- Or, simply delete the file (with Opera closed) and recreate it by launching Opera
To disable future searches from being retained:
- Set the 'search_field_history.dat' file to read only.