I have a web query that's working well when I'm importing a single datum into
a cell.
=SUMIF('Query Data'!$E:$E,$B23 & E$1,'Query Data'!$D:$D)

What I need to be able to do is to add the results of the query data of two
separate data (B23 and C23) into a single cell. Sometimes B23 will have data,
sometimes C23 will have data, sometimes both will.

I've tried ($B23+$C23) and ($B23:$C23) but get nothing, even when both have
data. Can someone help?