Perhaps you should try some spelling variations:
"dong hieu cach snippets" » "dung hieu cach snippets", "dong trieu cach snippets", "doc hieu cach snippets", "dong hieu cac snippets", "dong chieu sach snippets", "dong hieu ca 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 hieu cach 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 hieu cach snippets") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( dong hieu cach snippets ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("dong hieu cach snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))*.