I made a thread previously about Japanese search not working due to two reasons. One of those was fixed. Thanks! There is still one more issue that prevents Japanese search from working though that I hope can be fixed.
It is not possible to search in Japanese. The problem is the way Japanese text entry works and how the Deezer app handles it. It appears the Deezer app triggers a search after each character is entered. Unfortunately this breaks the text entry for Japanese. Japanese uses Chinese characters which are a combination of different phonetic sounds. How Japanese text entry works is you enter the phonetic characters, the keyboard provides suggestions for the Chinese characters that match those sounds, then you select the Chinese character you want. This changes the set of phonetic characters to the Chinese character. But since Deezer searches after each character is entered, the keyboard doesn't see the phonetic characters as a set and so doesn't provide suggestions for the Chinese character, and so they can't be selected and entered.
My proposed solution would be to give the user the option to disable auto search in the settings. I am guessing that if Deezer isn't searching every time a user enters a character then it won't interrupt Japanese text entry. It gives the added bonus of less hits to your databases or caches and uses less mobile data for the user.