I need a formula, (not sure if if(countif()) is the right one. I have column
data to look at. I put a filter on column c (blanks) and I need to find
records where there are rows inwhich cells in both column b and d are not
null.

for example

B1 = blue
C1 is null
D1 = yellow then the formula would return true. because the cells in B and
C are not null.