Perhaps you should try some spelling variations:
"cong trinh trong snippets" » "cong trinh truong snippets", "cong tranh trong snippets", "cong trinh trung snippets", "cong trinh trong 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.

• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"using _ code snippets\") OR (\"cong trinh trong snippets\"))) OR (\"locating bug code snippets\"))~".
• Removing quotes may allow a broader search: (((( using _ code snippets ) OR ( cong trinh trong snippets ))) OR ( locating bug code snippets ))~.
• Adding a wildcard symbol may retrieve word variants: (((("using _ code snippets") OR ("cong trinh trong snippets"))) OR ("locating bug code snippets"))*.