How can I make the "ITEMS detail search pop-up window" wider so I can see my stock items clearly

Welcome to the QuickBooks family, @ShopAdmin.

Currently, an option to make the products and services drop-down list wider is unavailable. Also, the system will only include the SKU information on the items depending on the details entered on the profile.

I appreciate every input you've provided, and I'll make sure to let our product engineers know about your suggestion. We constantly update the features in QuickBooks Online, and this preference might be added in the future.

While working on this, I suggest you visit our QuickBooks Blog to stay updated with all the changes that are being made. Additionally, I've attached an article you can visit to know more about migrating to QuickBooks Online:

What to expect when you switch from QuickBooks Desktop to QuickBooks Online.

Drop me a comment below if you have any other questions. I'll be more than happy to help. Wishing you a good one.

Thank you for your reply.

I think that this is a bigger problems as the same issue occurs when selcting Nominal accounts especially if you have made use of catergories.  Initially the pick list is wide.....but as you type and it tries to filter down the windows is drastically reduced and the same issue occurs