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