Sonething strange with filtering

[da411d]

My table is

Array
(
    [0] => Array
        (
            [Date] => 2015-11-04
            [Time] => 18:07
            [LastEdit] => 00:00
            [Subject] => it
            [Class] => 31
            [Student] => vikakozun
            [Teacher] => dersm
            [Mark] => 7
            [Info] => ахахахахах
        )

    [1] => Array
        (
            [Date] => 2015-11-04
            [Time] => 18:07
            [LastEdit] => 00:00
            [Subject] => it
            [Class] => 31
            [Student] => da411d
            [Teacher] => dersm
            [Mark] => 12
            [Info] => -
        )

    [2] => Array
        (
            [Date] => 2015-11-04
            [Time] => 18:07
            [LastEdit] => 00:00
            [Subject] => it
            [Class] => 31
            [Student] => da411d
            [Teacher] => dersm
            [Mark] => 12
            [Info] => 
        )

    [3] => Array
        (
            [Date] => 2015-11-04
            [Time] => 18:07
            [LastEdit] => 00:00
            [Subject] => it
            [Class] => 31
            [Student] => da411d
            [Teacher] => dersm
            [Mark] => 12
            [Info] => 
        )

    [4] => Array
        (
            [Date] => 2015-11-04
            [Time] => 18:07
            [LastEdit] => 00:00
            [Subject] => it
            [Class] => 31
            [Student] => vikakozun
            [Teacher] => dersm
            [Mark] => 1
            [Info] => rgersdgvs
        )
...
)

If i type

$database->select("marks", 
    ["Date", "Time", "LastEdit", "Subject", "Class", "Student", "Teacher", "Mark", "Info"],
    ["Student[=]" => 'da411d']
)

everything is good. If i type

$database->select("marks", 
    ["Date", "Time", "LastEdit", "Subject", "Class", "Student", "Teacher", "Mark", "Info"],
    ["Subject[=]" => 'it']
)

everything is also good.

But when i type

$database->select("marks", 
    ["Date", "Time", "LastEdit", "Subject", "Class", "Student", "Teacher", "Mark", "Info"],
    ["Student[=]" => 'da411d', "Subject[=]" => 'it']
)

it returns nothing:(

[SyuTingSong]

Use AND to combine your conditions

$database->select("marks", 
    ["Date", "Time", "LastEdit", "Subject", "Class", "Student", "Teacher", "Mark", "Info"],
    [
        'AND' => [
            "Student[=]" => 'da411d',
             "Subject[=]" => 'it'
        ]
    ]
);

Use OR to combine your conditions

$database->select("marks", 
    ["Date", "Time", "LastEdit", "Subject", "Class", "Student", "Teacher", "Mark", "Info"],
    [
        'OR' => [
            "Student[=]" => 'da411d',
             "Subject[=]" => 'it'
        ]
    ]
);

[SyuTingSong]

See the Chapter Relativity Condition in http://medoo.in/api/where

[da411d]

Thanks