Excel function

so im trying to get this function down, but im not to good at it.

lets say im looking at cell S2 - U2. 2 of them will say "OTHER", one will not. how do i tell V2 to copy the one that does not say "OTHER" when i dont know what it will say?

uh, im not seeing "when" as a function. and what does the "str" stand for?