У вас есть два где ... но вы должны использовать только одно использование ИЛИ
SQL = "SELECT tblPartsAndConsumables.[DESCRIPTION], tblPartsAndConsumables.[P/N], tblPartsAndConsumables.[S/N], tblPartsAndConsumables.[B/N], tblPartsAndConsumables.QTY, tblPartsAndConsumables.[EXPIRY DATE], tblPartsAndConsumables.LOCATION, tblPartsAndConsumables.Attachments " _
& " FROM tblPartsAndConsumables " _
& "WHERE [Customer Name] LIKE '*" & Me.CustomerListbox.Value & "*' " _
& " OR [DESCRIPTION] LIKE '*" & Me.Searchbox & "*' " _
& "OR [P/N] LIKE '*" & Me.Searchbox & "*' " _
& "OR [S/N] LIKE '*" & Me.Searchbox & "*' " _
& "OR [B/N] LIKE '*" & Me.Searchbox & "*'" _
& " ORDER BY tblPartsAndConsumables.[DESCRIPTION], tblPartsAndConsumables.[P/N]; "
Если предложение "здесь" должно работать вместе, вам нужно И, например: "
SQL = "SELECT tblPartsAndConsumables.[DESCRIPTION], tblPartsAndConsumables.[P/N], tblPartsAndConsumables.[S/N], tblPartsAndConsumables.[B/N], tblPartsAndConsumables.QTY, tblPartsAndConsumables.[EXPIRY DATE], tblPartsAndConsumables.LOCATION, tblPartsAndConsumables.Attachments " _
& " FROM tblPartsAndConsumables " _
& "WHERE [Customer Name] LIKE '*" & Me.CustomerListbox.Value & "*' " _
& " AND [DESCRIPTION] LIKE '*" & Me.Searchbox & "*' " _
& " ADN ( [P/N] LIKE '*" & Me.Searchbox & "*' " _
& "OR [S/N] LIKE '*" & Me.Searchbox & "*' " _
& "OR [B/N] LIKE '*" & Me.Searchbox & "*' )" _
& " ORDER BY tblPartsAndConsumables.[DESCRIPTION], tblPartsAndConsumables.[P/N]; "
ИЛИ
SQL = "SELECT tblPartsAndConsumables.[DESCRIPTION], tblPartsAndConsumables.[P/N], tblPartsAndConsumables.[S/N], tblPartsAndConsumables.[B/N], tblPartsAndConsumables.QTY, tblPartsAndConsumables.[EXPIRY DATE], tblPartsAndConsumables.LOCATION, tblPartsAndConsumables.Attachments " _
& " FROM tblPartsAndConsumables " _
& "WHERE [Customer Name] LIKE '*" & Me.CustomerListbox.Value & "*' " _
& " AND ( [DESCRIPTION] LIKE '*" & Me.Searchbox & "*' " _
& " OR [P/N] LIKE '*" & Me.Searchbox & "*' " _
& "OR [S/N] LIKE '*" & Me.Searchbox & "*' " _
& "OR [B/N] LIKE '*" & Me.Searchbox & "*' )" _
& " ORDER BY tblPartsAndConsumables.[DESCRIPTION], tblPartsAndConsumables.[P/N]; "