Acrobat seems to start search after 3 characters resulting in findings containing these 3 character

Acrobat start searching immediately after a certain amount (3??) characters are typed in the search field. Depending on document size it seems to ignore any additional typed in character which completes the 3 chars to the actual intended search string.

This results in

A) a delayed appearance of further typed characters in the search field, since Acrobat is busy with searching

B) search result containing only these first 3 typed characters ignoring following characters

Example:

search string is "diagram"

Acrobat starts search after "dia" is typed in and any further character "gram" is not seen since input is blocked. If search is finished or due to any other reason the input is accepted again, I can add missing character "gram". However as results I see "findings" like "diameter", "dialogue" and even "diagram" and obviously string "gram" all starting from 4th position is ignored.

Deleting last character(s) and typing in again dose not help. Search is not updated.

Only help is to cut and paste the whole search string (to be fast enough before autosearch starts).

How can I fix this, i.e. force Acrobat to start search if I hit the search button previous/next (or "Zurück" & "Weiter", because I have German edition)?

For a 10 pages document this might not be an issue but I deal with docs having 5000+ or 7000+ pages. This behaviour is annoying!