Perhaps you should try some spelling variations:
"dong nang cai snippets" » "dong bang cai snippets", "dung nang cai snippets", "dong yang cai snippets", "dong nang cao snippets", "dong nang tai snippets", "dong nang cap 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 nang cai 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 nang cai snippets") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( dong nang cai snippets ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("dong nang cai snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))*.