font break issue 2

I already asked the same issue, but I have more questions, please check it again.

(Original ask)

After converting the file, the connection program is selected as "Adobe Reader", and the characters are broken.

(The same file association program converted from Autovue is not broken with Google Chrome)

But the only problem is when I use the "Malgun Gothic(맑은 고딕)" and bold effects.

Each of the Malgun Gothic and Bold effects can be used but is a problem when used together.

Actually, this is my customer situation. I tried it on my computer and the characters in Adobe Reader(free version) did not break.

Customers say they are using genuine Adobe products, so could you let me know how can solve this issue?

(added ask)

I confirmed that Adobe Reader version is 2018.009.20050. I also confirmed that there is a Malgun gothic with bold effect in the property where the letter is broken. In addition, this it does not occur unless the bold effect is given  Malgun gothic.

The conversion of pdf was done by Auto-View product of Oracle Corporation.

I would be grateful  let me know what causes the problem.

In addition, the same version of Adobe Reader did not break text.

It looked the same when I checked the font properties (File> Properties> Font).

Please check it out by reference.