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