If you have a global field to enter in your "hammer" (gEntry), then you can script it to search both fields.
Enter Find Mode 
Set Field [ general description; gEntry ]
Set Field [ detailed description; gEntry ]
Perform Find 
Not sure if that will work or not, I don't want to set/change the two fields.
For example, someone might be looking for a specific saw. They might search "saw", which all of our many types of saws are listed under, but they may also search "hydraulic concrete saw", which is listed only under "detailed description" field. If the find is set up for searching the "general desc" field, then "hydraulic concrete saw" wouldn't work. However, if the find was searching both the general and detailed desc, this "hydraulic concrete saw" search would work.
Try Mr. Vodka's example. It should work for you.
The set fields are operating while in find mode so no data is actually being changed. The new request step puts the find criteria in two different request instances. The logic works as an "OR" operation. If "saw" is in first field OR the second field, it will be found.
That definitely worked! Thanks for the solution.
I have one quick follow up question though.
When I open the layout, it lists all my records in a list. Is there a way to not show any records unless I perform a find?
The reason is, these finds will be performed on handhelds through IWP, and therefore loading 1000's of records will waste time.
The following script will generate an empty found set and thus display no records:
Go To Layout [layout where you want to show zero records]
Show all records
Show omitted Only