According to Ali ibn abi Talib to retain in memory whatever one listens or reads, recite the following dua'a after every obligatory salat
SUBH'AANA MAN LAA YA-TADEE AA'LAA AHLI MAMLAKATIHEE SUBH'AANA MAN LAA YAAKHUD'U AHLAL ARZ'I BILWAANIL A'D'AABI SUBH'AANAR RA-OOFIR RAH'EEMI ALLAAHUMMAJ-A'L LEE FEE QALBEE NOORAN WA BAS'ARAN WA FAHMAN WA I'LMAN INNAKA A'LAA KULLI SHAY-IN QADEER

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