Hi There - I think I have understood what you are trying to point out
In the case of Sales Order item, I can see that whenever you type something multiple results containing that text/description show up. That's how lookup searches work in Business Central. When you type "CB08" all items having CB08 anywhere in them will start showing up in the list below you. It's the user's job to select the accurate item with the help of a mouse click, from that drop down list. You either type the whole item code AS-IT-IS present on the item card, or type closely related numbers and click from the list when you see the one you wanted
If you type CB08 and just press tab, the search will pick up whatever it has found first. It thus becomes imperative to select the correct item number from the drop down
However, there's another way to assist to make your item entry faster/efficient
1. Create a sales order. Populate the customer
2. On the lines, there will be a button called "Select Items". It should be under "Manage". A list of all items will open
3. On this list, you can search the your item from the page search given on top. Once you locate your item, you need to select it. You can select multiple or 1, depends on you
4. Now you can press OK, your lines on the sales order will be populated with the item/items you selected
For Deposits:
The document number is auto-generated from the BC setup of number sequences, I would suggest not to alter that. Rather see if you can find a column for entering your check number, the column should be named "External document no". You can enter your check references in this column
Also, since you are adding multiple customers into one deposit, the document numbers are unlikely to change. Create different deposits if you need different document numbers
