In this instance, I have decided that key terms include the statute (which I have formulated as "11 U.S.C. /3 522" to pick up instances of "section 522 of 11 U.S.C."  as well as "11 U.S.C. 522) and "profit sharing plan" (which is a term of art).  From the problem, I deduce that a key issue is whether  the plan was sponsored by a single shareholder.  Consequently, I use the "or" command to pick up synonyms (of "single shareholder") as well as several groupings of parentheticals to control the order of operation.  In addition, I use a universal extender to pick up plurals (although technically both Lexis and Westlaw will automatically search for plurals).  Finally, I make sure to restrict the dates of the search to after 1989.  In Westlaw, remember to access date restrictions in the "Field Restrictions" link highlighted below.