SELECT CustID, CustName, CustAddress, CustPostcode, CustTel, CustEmail, CustNotes, CustRoom, CustStayArrive, CustStayLeave
FROM tblCustData
WHERE CustName = '" & SearchBox.Text & "'
Change the last line to
WHERE CustName like '%" & SearchBox.Text & "%'
where the % is the wild card character...