Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets"
"khi moi hoc snippets" » "thi moi hoc snippets", "khi doi hoc snippets", "khi hoi hoc snippets", "khi mon hoc snippets", "khi mo hoc 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: (((("khi moi hoc snippets") or ("python using java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("khi moi hoc snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( khi moi hoc snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("khi moi hoc snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.