Perhaps you should try some spelling variations:
"tang van code snippets" » "tang van de snippets", "tang van hoe snippets", "tang van cong snippets", "dang van code snippets", "hoang van code snippets", "trong van code snippets", "tang van code slippers"
"cong trinh java snippets" » "cong trinh java slippers"
"locating bug code snippets" » "locating bug code slippers", "locating bung code snippets", "locating bugs code 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 trinh java snippets") or ("tang van code snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("cong trinh java snippets") OR ("tang van code snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( cong trinh java snippets ) or ( tang van code snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("cong trinh java snippets") or ("tang van code snippets"))) or ("locating bug code snippets"))*.