Perhaps you should try some spelling variations:
"support china international seminar." » "support china international standard.", "support china international journal.", "support china international air.", "support china's international seminar.", "report china international seminar."
"supply large irrigation systems." » "supply farm irrigation systems.", "supply drip irrigation systems.", "supply scale irrigation systems.", "supply charges irrigation systems.", "supply market irrigation systems.", "supply curve irrigation systems.", "supply large irrigation system."

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (("supply large irrigation systems.") or ("support china international seminar."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("supply large irrigation systems.") OR ("support china international seminar.")).
• Removing quotes may allow a broader search: (( supply large irrigation systems. ) or ( support china international seminar. )).
• Adding a wildcard symbol may retrieve word variants: (("supply large irrigation systems.") or ("support china international seminar."))*.