I am trying to compare four columns of text, say A-D, such that if the paired
combination of cells A2 and B2 can be found as a combination of the same pair
text ANYWHERE in columns C and D, I would get "true". I.e., I want to search
for all the A+B combos in corresponding C+D columns
example:

A B C D E
1 oak tree bird dog true
2 gold brick oak brick false
3 dumb bunny oak tree false

The process found the combination for A1+B1 in C3+D3; I would want to do
the same for gold+brick and dumb+bunny, etc.etc. Geez I'm worn out trying
different combos of "logic."