An application sends a ZGM_MARKTEXT to mark the text that contains the given string.
wParam = 0; //not used; must be zero
lParam = (LPARAM) lpszString; //address of string to match
The number of cells that matched the text in lpstring.
The return value indicates the number of matches in visible cells. Cells that match the text but are in columns that are sized to a width of zero will not be marked, and are not returned in the match count.