@peterrc

"Select a Cell D2 (formula), click fx to the left of the formula (in the formula bar), select either argument and row 7 is selected (wrong)."

Actually, the result of 7 for the evaluation of this part of the formula: MATCH(TRUE,INDEX(ISNUMBER(SEARCH(A:A,B2)),,),0) that the OP currently has in cell D2 is perfectly correct. It's just that it's the wrong formula for what they want to do!

It is, in effect, asking for the row number of the first entry in column A which can be found within the string in cell B2. None of the entries in rows 1-6 meet that criteria; however, the entry in the 7th row (a blank) is to be found within the string in B2, and hence the result of 7.

Regards