Change Safari search suggestions language on iPhone
Welcome to the Non-World Wide Web !

In the good old days, search engines respected the principles of the World Wide Web. Then they started to alter their outputs according to guessed language and guessed location. 

Your problem comes from the search engine used by Safari : Google or Bing or another one.

You may try these possible solutions : 


Go to the Web site of the search engine, and look into its prefs. 
Write to the search engine’s editor. And be patient. 
Switch Safari to another search engine. 
Use a proxy to disguise your location. I don’t recommend this workaround, it is dirty, we shouldn’t have to do this.