Lookup spareparts long(er) text

With the minimum on characters that can be used for material descriptions or vendor references , it's not always easy to find a good solutions where to add "search strings". Splitting this up in different fields causes a lot of explaining and work for the technicians. Is there any way to add several "search strings" into the "Info Memo" record ? And search in this field ? Other suggestions where we can have a look up possibility ? In fields larger then 40 characters ?