Perhaps you should try some spelling variations:
"van hung duoc slippery" » "van cung duoc slippery", "van thuong duoc slippery", "van nhung cuoc slippery", "van dung duoc slippery", "manh hung duoc slippery", "van duong duoc slippery", "van hung duoc slippers"
"python using a snippets" » "python using a 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.

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