Perhaps you should try some spelling variations:
"using java code snippets" » "using data code snippets", "using java core snippets"
"van tuan de snippets" » "van quan de snippets", "van ban de snippets", "anh tuan de snippets", "van tuan le snippets", "van luan de snippets", "van toan de snippets"
"locating bug code snippets" » "locating bug core 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 snippets") or ("van tuan de snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("using java code snippets") OR ("van tuan de snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( using java code snippets ) or ( van tuan de snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("using java code snippets") or ("van tuan de snippets"))) or ("locating bug code snippets"))*.