Hi Giang, 
I suggest opening a support ticked for guidance, this way we can review what has already been done and advise on what next steps are needed.

From your example you're likely missing values in your entry transaction screens, where you can also set visibility per entry transaction.

Please keep in mind that customizations are not supported but handled by your business partner and/or your local CoEx team.

Thanks 

I'm not sure if this is what you need but i looked at our custom fields and they were not on the associated transaction entry screen.   

I found this.  Old but it might apply.  I did not test it.    They mentioned adding the code snippet to the transaction screen.  I suspect something like this code is required. 

Handling the Customized Fields Using Entry Transaction in Sage X3 - Sage X3 – Tips, Tricks and Components (greytrix.com)

5. Refer following snippet of code to make work:
# prix brut
If [M:SLC3]ZCUSTCOD > 1 TZONE(IZON)="ZCUST"
TMOD(IZON) =[M:SLC3]ZCUSTCOD IZON+=1
Endif
If [M:SLC3]ZCUSTCOD = 1 | [M:SLC3]ZCUSTCOD = 2
ZT="ZCUSTSCR" : ZM="ZCUST" : Gosub TABLEAU_FICHE From SUBSLX Endif

Hi Stephen

Thanks so much for your advice,

Do you know where to put the snippet code (step 5)?

>>Do you know where to put the snippet code (step 5)

NO.  I have not tried this.  I would assume it goes in the SPESIH, or specific script, of the sales invoice screen SIH. 

The sample is of course NOT for the field's you are adding.