Perhaps you should try some spelling variations:
"using java code slippers" » "using data code slippers"
"duc trinh viet snippets" » "duc ninh viet snippets", "duc trinh vat snippets", "duc thinh viet snippets", "doc trinh viet snippets", "qua trinh viet snippets"
"locating bug code snippets" » "locating bung code snippets", "locating bugs code 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: (((("using java code slippers") or ("duc trinh viet snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("using java code slippers") OR ("duc trinh viet snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( using java code slippers ) or ( duc trinh viet snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("using java code slippers") or ("duc trinh viet snippets"))) or ("locating bug code snippets"))*.