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The sales order or invoice or shipping or purchase order is open - you have already entered the header details (i.e. customer details, supplier details, order number, etc)
To search on parts of words anywhere in the product name. Just enter the required words. For example to find all red A4 paper type in "red A4 paper" or "A4 Paper Red". All products having those words anywhere in their name will be found.
Left click into the Product code field.
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