Perhaps you should try some spelling variations:
"using java code snippets" » "using data code snippets", "using java core snippets", "using java code slippers"
"dan pham trong snippets" » "dan pham thuong snippets", "dan pham cong snippets", "dan nam trong snippets", "san pham trong snippets", "dan phan trong snippets", "van pham trong snippets", "dan pham trong slippers"
"locating bug code snippets" » "locating bug core snippets", "locating bug code slippers", "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 snippets") or ("dan pham trong snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("using java code snippets") OR ("dan pham trong snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( using java code snippets ) or ( dan pham trong snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("using java code snippets") or ("dan pham trong snippets"))) or ("locating bug code snippets"))*.