I am very confused. I keep playing well in Europe and my nation keeps getting worse

I play in Bulgaria and at the start my league reputation is 110.

First year all 4 bulgarian teams played in Europe Group and I managed to go to 1/16 final to it .

That means there were a lot of wins from my side but the computer failed in the groups.

I see the league rises up to 22 place and I say great. I check Coeficients and I have like 16th coeficient by Nation

Next year one of the team plays in Group Phase in Champions League and I again reach 1/16 final and the reputation sucumbs do 50 place..Although my rankings for the year is liek 10th place in Europe by nation i mean.

Last year I manage to go to 1/2 final in EURO Cup the other teams failed in quilify but still I did great and I increase only to 38 position .

I say ok its myabe realistic but then I check my neigbours in Romania last year they went from 40th to 20t position and they coefficeint for the year is 2.75 and my is 8.00.

Why the hell their league is so much better when they failed badly ?

Their natioanl team also failed badly just like Bulgarian one