How to add serial number to sales invoice ,we got multiple products.

Hello
1)How to add serial number to sales invoice ,we got multiple products.
2)How to resize the columns in sales invoice

please search the forum and read the guides section before posting new questions.

read this guide Manager Cloud

all columns in Manager are automatically wrapped according to the text content. why do you want to resize it?

Are you referring to line numbers on the invoice, as interpreted by @sharpdrivetek? Or are you referring to serial numbers of the products themselves?

If the latter, you can add a line-item custom field for sales invoices that allows you to enter the serial number of the specific item sold. But you cannot track serial numbers of inventory items unless each one is a separate inventory item. Manager assumes all units of an inventory item are interchangeable.