I have a problem with exloding dice, and "keep" macro. (I need exploding advantage macro.)

Ok, first of all I need to give some context of what am I trying to do:

In one of my 5e campain I have a special rule where players forced to take feat instead of ASI, but if they want they can use downtime to improve on their attributes.

The important part of it is following: Players can stack advantage and have an exploding die on top of it.

Example of the macro: /roll 4d20!k1+2 (4d stand for advantage*2+luck, 20! set for explode, k1 works as keep the highest number, +2 example of current attribute modifier)

The problem is that "keep" function ignores The next dice after explosion. (example result:   for result of... 22).

I want macro to include 17 in result, but "keep" function is not helping here.

-"Well one option to keep rolling d20!+2 4 times for each in game day and do all the math yourself right? RIGHT?!"

-Ye, now do it for 4 in game MONTH why dont'cha?!

Here's my month macro: 120d20!k30+2*30 (30days*4d's=120d20's, !for exploding, k30 for keep the highest result which if flawed, +2*30 for AS*number if days) AND HERE IS HFIL I have to deal with...

Please help before I have to turn insanity system on just for myself...

TLDR: How do I advantage exploding dice?

This looks like it works for 4x Adv

[[ {1d20!+2,1d20!+2, 1d20!+2, 1d20!+2}kh1 ]]

EDIT - I'm not sure what your 120 roll thing is all about, but I believe the following should roll 120d20!+2 and keep the highest 30 rolls. (I built the string in Excel using the =REPT() formula)

[[{1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2,1d20!+2}kh30]]

The compound exploding dice modifier seems perfect for this situation which is !! instead of !. it combines the exploding dice into a single value so when you keep 1 in your 4d20 example it would have kept the 20 and the 17 as a single value. So your 4d20 macro would be

/roll 4d20!!k1+2

and your month macro

/roll 120d20!!k30+2*30

Thanks for the help! Some of my players are really get turned off by braining numbers.

Here's "improvement" system i was working on, feel free to scrap it!
PC have to spent 8h per day to attempt to improve skill. PC have to RP the initial process. (i.e. explain how they improve)

PC must have 0 exhaustion to begin.

PC gain stacking advantage for:

1. spending 12h for it (PC is busy for all day as trade-off);

2. finding teacher (NPC\PC with higher stats who will to spend time with PC)

3. Team-up with another NPC\PC (they have to improve same ASI at same level)

4. PC can use one luck point, and it is assumed he's doing so.

The number you got counts as EXP toward the 1 ASI point.

The amount of exp needed i recommend to setup manually.

Example: Assumed the roll will be 15 average PC will need to spend 1 year to gain ASI to 18, 15*365=5475 exp required.

That's all folks! Thanks again, and have a nice day!