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