Perhaps you should try some spelling variations:
"locating bug core snippets" » "locating bug code snippets"
"python using data snippets" » "python using java snippets", "python using sat snippets", "python missing data snippets"
"cho vien dai snippets" » "cho viec dai snippets", "cho vienam dai snippets", "chuc vien dai snippets", "cho hien dai 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: (((("cho vien dai snippets") or ("python using data snippets"))) or ("locating bug core snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("cho vien dai snippets") OR ("python using data snippets"))) OR ("locating bug core snippets")).
• Removing quotes may allow a broader search: (((( cho vien dai snippets ) or ( python using data snippets ))) or ( locating bug core snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("cho vien dai snippets") or ("python using data snippets"))) or ("locating bug core snippets"))*.