Perhaps you should try some spelling variations:
"trung dai cong snippets" » "truong dai cong snippets", "truong dao cong snippets", "trung tam cong snippets", "trung dai cuong snippets", "trung tai cong snippets", "trung doi cong snippets"
"dung java java snippets" » "dung va java snippets"
"locating bug code snippets" » "locating bung code snippets", "locating bugs code snippets", "locating bug core snippets"

Try widening your search to All Fields.

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

• Performing a fuzzy search may retrieve terms with similar spellings: (((("trung dai cong snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("trung dai cong snippets") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( trung dai cong snippets ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("trung dai cong snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))*.