Perhaps you should try some spelling variations:
"dong lieu da snippets" » "dong hieu da snippets", "dong dieu da snippets", "dong tieu da snippets", "dong lieu dao snippets", "dong lieu dai snippets", "dong lieu dia 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 lieu da 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 lieu da snippets") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( dong lieu da snippets ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("dong lieu da snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))*.