Perhaps you should try some spelling variations:
"cong trinh van snippets" » "cong trinh han snippets", "cong trinh quan snippets", "cong trinh toan snippets", "cong trinh van slippers"
"using _ code snippets" » "using _ code slippers"
"locating bug code snippets" » "locating bug code slippers", "locating bung code snippets", "locating bugs code snippets"

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

• If you are trying to use Boolean operators, they must be ALL CAPS: (((("using _ code snippets") OR ("cong trinh van snippets"))) OR ("locating bug code snippets"))~.
• Removing quotes may allow a broader search: (((( using _ code snippets ) or ( cong trinh van snippets ))) or ( locating bug code snippets ))~.
• Adding a wildcard symbol may retrieve word variants: (((("using _ code snippets") or ("cong trinh van snippets"))) or ("locating bug code snippets"))*.