Search engine added,  more simple messages

Done
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1. search engine added. That can find team or project. ( It is needed to update for join team or project by UI ) 
2. more simple messages
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Required
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1. Test code for search engine ( Not yet because how the user apply to join team or project from search engine is not decided. )
2. request to join team or project from searched object ( from the result of the search engine)