Perhaps you should try some spelling variations:
"van van thanh slippery" » "van ban thanh slippery", "van van tuan slippery", "tan van thanh slippery", "san van thanh slippery", "van van thanh 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"

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