Perhaps you should try some spelling variations:
"van van trinh slippers" » "van van thinh slippers", "van van tinh slippers", "van dan trinh slippers", "van ban trinh slippers", "tan van trinh slippers", "san van trinh slippers", "van van trinh slippery", "van van trinh grippers"
"dung java java snippets" » "dung va java snippets"
"locating bug code snippets" » "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: (((("van van trinh slippers") or ("dung java java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("van van trinh slippers") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( van van trinh slippers ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("van van trinh slippers") or ("dung java java snippets"))) or ("locating bug code snippets"))*.