I experimented with a dummy database and discovered that after turning off the “Search as formatted” option, the option remained off for subsequent searches.
If you are in a form when the search is initiated, you could then create a command button to initiate the search. Use the wizard to create a search action on the Click event and let it set up the DoCmd.FindRecord command line. The default is to set Search as formated to False.
The VBA help topic “FindRecord Method” shows the complete description of the command line options:
expression.FindRecord(FindWhat, Match, MatchCase, Search, SearchAsFormatted, OnlyCurrentField, FindFirst)