str.contains() returns a Series of booleans that we can use to index our frame
patternDel = "( \\((MoM|QoQ)\\))"
filter = df['Event Name'].str.contains(patternDel)
I tend to keep the things we want as opposed to delete rows. Since filter represents things we want to delete we use ~ to get all the rows that don’t match and keep them
df = df[~filter]