Perhaps you should try some spelling variations:
"dong quan doc snippets" » "duong quan doc snippets", "dong quang doc snippets", "dung quan doc snippets", "dong quan doi snippets", "dong quan dac snippets", "dong quan doan 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: (((("dong quan doc snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("dong quan doc snippets") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( dong quan doc snippets ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("dong quan doc snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))*.