Perhaps you should try some spelling variations:
"va trinh luan snippets" » "va trinh luat snippets", "va trinh quan snippets", "va trinh han snippets", "van trinh luan snippets", "va tinh luan snippets", "lap trinh luan snippets", "va trinh luan slippers"
"using real java snippets" » "using metal java snippets", "using raw java snippets", "using real java slippers"
"locating bug code snippets" » "locating bug code slippers", "locating bung code snippets", "locating bugs code snippets", "locating bug core snippets"

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (((("va trinh luan snippets") or ("using real java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("va trinh luan snippets") OR ("using real java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( va trinh luan snippets ) or ( using real java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("va trinh luan snippets") or ("using real java snippets"))) or ("locating bug code snippets"))*.