The code you displayed might not be the actual code. Where did those white things come from?
According to the docs, it will not return the subexpression unless you set the returnsubexpression flag to true. If the flag is false (default), it retuns an array of length and position of the subexpression.
<cfset xyz='Surplus Percentage Total in the Amount of $2000.00'>
<cfset foundword = REFindNoCase('Percentage',xyz)>
<cfif foundword GT 0>
Word found at position <cfoutput>#foundword#</cfoutput>
Word not found
Thanks.... implemented already with the RefindNocase. The values were coming in either lower/Upper case realized I have to use RefindNocase