Perhaps you should try some spelling variations:
"using java code snippets" » "using data code snippets", "using java core snippets"
"tao danh toc snippets" » "cao danh toc snippets", "tac danh toc snippets", "tao anh toc snippets", "tao dan toc snippets", "tao danh hoc snippets", "tao danh thuc 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 ("tao danh toc snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("using java code snippets") OR ("tao danh toc snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( using java code snippets ) or ( tao danh toc snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("using java code snippets") or ("tao danh toc snippets"))) or ("locating bug code snippets"))*.