Perhaps you should try some spelling variations:
"cong tang ca snippets" » "cong thang ca snippets", "cong tan ca snippets", "cong lang ca snippets", "cong tang cua snippets", "cong hang ca snippets", "cong tang ma 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: (((("cong tang ca snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("cong tang ca snippets") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( cong tang ca snippets ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("cong tang ca snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))*.