Use like Find when you are searching for a line label.
 
When using Label, the QBX environment looks only at the
first nonblank item in a program text line that ends with a
colon.
 
Note: When you enter the search label into the Find What
      text box, do NOT include the colon. BASICA-style
      integer line labels are not followed by colons,
      so you cannot use Label to locate them.