Perhaps you should try some spelling variations:
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"basicas matematicas computer programs." » "basicas mathematics computer programs.", "basicas matematicas como programs.", "basicas matematicas comics programs.", "comicas matematicas computer programs.", "benditas matematicas computer programs.", "fisica matematica computer programs.", "basicas matematicas computer programas.", "basicas matematicas computer programa."

Try widening your search to All Fields.

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• Performing a fuzzy search may retrieve terms with similar spellings: (("competencias matematicas computer programmers.") or ("basicas matematicas computer programs."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("competencias matematicas computer programmers.") OR ("basicas matematicas computer programs.")).
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• Adding a wildcard symbol may retrieve word variants: (("competencias matematicas computer programmers.") or ("basicas matematicas computer programs."))*.