Perhaps you should try some spelling variations:
"python missing data snippets" » "python using data snippets"
"locating bug core snippets" » "locating bug code snippets"
"cu van dau snippets" » "cu van dao snippets", "cu phan dau snippets", "cuu van dau snippets", "chu van dau snippets", "cau van dau snippets"

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (((("python missing data snippets") OR ("cu van dau snippets"))) OR ("locating bug core snippets"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"python missing data snippets\") OR (\"cu van dau snippets\"))) OR (\"locating bug core snippets\"))".
• Removing quotes may allow a broader search: (((( python missing data snippets ) OR ( cu van dau snippets ))) OR ( locating bug core snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("python missing data snippets") OR ("cu van dau snippets"))) OR ("locating bug core snippets"))*.