Filter out duplicates in excel spreadsheet. -

i have several thousand rows , handful of them appear more 1 time. need able filter out review them without scrolling through thousands of rows of data.

my data strings can't use math calculation (at least don't know how could). need data return in instance seattle symphony (all 3 times).

atlanta symphony orchestra kingston symphony seattle symphony seattle symphony seattle symphony orchestra of st. luke's pasadena symphony association 

how say, please return rows appear multiple times. thank you.

in column, starting in row 2 (because row 1 should header row), use formula , copy down (this formula assumes symphony names in column a):

=countif(a:a,a2)>1 

then filter on column true