Your search will be greatly focussed by the addition of quotes. Use capital letters for proper names. This can greatly increase the relevancy of your search results. Check your spelling. Try different words that mean the same thing.
Some search engines allow complex searches using combinations of many terms.
Each search engine has software which constantly roams the Web to gather sites for its unique index. Each search engine gathers sites at its own rate in its own way. Search engine indexes are updated at different schedules. New sites show up in search engine databases at different times. Your search term may be relevant in one search engine database and not so relevant in another.