These commands can only be accessed after you enable support for Asian languages in LibreOffice - PreferencesTools - Options - Languages and Locales - General.
བཀའ་ཚིག་ལ་བཅར་འདྲི་...
Choose LibreOffice - PreferencesTools - Options - Languages and Locales - Searching in Japanese.
དེ་གཅིག་མཚུངས་སུ་འཇོག་པ།
Specifies the options to be treated as equal in a search.