Align controls based on android device screen

Question

I have a Samsung Tab 4 tablet, the layout looks great on a big device screen, but when i put it on landscape or change the device to a smaller one, all controls goes out of devices screen. I'm kinnda new to Android and your help will be great for me. This is my .xml file, how can i anchor elements to fit to any device screen?

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:htext="http://schemas.android.com/apk/res-auto"
android:id="@+id/welcome_fragment"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@color/background"
android:clipChildren="false"

android:orientation="vertical"
android:paddingTop="48dp"
android:weightSum="6">

<com.hanks.htextview.HTextView
    android:id="@+id/hBunaZiua"
    android:layout_width="match_parent"
    android:layout_height="100dp"
    android:layout_marginTop="40dp"
    android:background="@color/background"
    android:gravity="center"
    android:textColor="@color/primary"
    android:textSize="30dp"
    htext:animateType="anvil" />

<com.hanks.htextview.HTextView
    android:id="@+id/hVenim"
    android:layout_width="match_parent"
    android:layout_height="100dp"
    android:layout_below="@+id/hBunaZiua"
    android:background="@color/background"
    android:gravity="center"
    android:textColor="@color/primary"
    android:textSize="20dp"
    htext:animateType="anvil" />


<LinearLayout
    android:id="@+id/layout1"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:visibility="invisible"
    android:orientation="horizontal">

    <ImageView
        android:id="@+id/outstorebill"
        android:layout_width="100dp"
        android:layout_height="70dp"
        android:layout_below="@+id/hVenim"
        android:layout_marginLeft="20dp"
        android:src="@drawable/outstorebill" />

    <TextView
        android:id="@+id/tvOutstorebill"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_weight="1"
        android:gravity="center|center_horizontal"
        android:paddingLeft="24dp"
        android:paddingRight="24dp"

        android:text="@string/slide1par1"
        android:textColor="@color/primary"
        android:textSize="15sp" />
</LinearLayout>


<LinearLayout
    android:id="@+id/layout2"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_marginTop="30dp"
    android:visibility="invisible"
    android:orientation="horizontal">

    <ImageView
        android:id="@+id/virtualbill"
        android:layout_width="100dp"
        android:layout_height="70dp"
        android:layout_below="@+id/outstorebill"
        android:layout_marginLeft="20dp"
        android:src="@drawable/virtualbill" />

    <TextView
        android:id="@+id/tvVirtualbill"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_weight="1"
        android:gravity="center|center_horizontal"
        android:paddingLeft="24dp"
        android:paddingRight="24dp"
        android:text="@string/slide1par2"
        android:textColor="@color/primary"
        android:textSize="15sp" />

</LinearLayout>


<LinearLayout
    android:id="@+id/layout3"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_marginTop="30dp"
    android:visibility="invisible"
    android:orientation="horizontal">

    <ImageView
        android:id="@+id/physicalbill"
        android:layout_width="100dp"
        android:layout_height="70dp"
        android:layout_below="@+id/virtualbill"
        android:layout_marginLeft="20dp"
        android:src="@drawable/physicalbill" />

    <TextView
        android:id="@+id/tvPysicalbill"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_weight="1"
        android:gravity="center|center_horizontal"
        android:paddingLeft="24dp"
        android:paddingRight="24dp"
        android:text="@string/slide1par3"
        android:textColor="@color/primary"
        android:textSize="15sp" />

</LinearLayout>

<LinearLayout
    android:id="@+id/layout4"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:visibility="invisible"
    android:orientation="horizontal"
    android:layout_marginTop="30dp"
    >

    <TextView
        android:id="@+id/tvnotificare"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_weight="1"
        android:gravity="center|center_horizontal"
        android:paddingLeft="24dp"
        android:paddingRight="24dp"
        android:text="@string/slide1par4"
        android:textColor="@color/primary"
        android:textSize="15sp" />
</LinearLayout>

<LinearLayout
    android:id="@+id/layout5"
    android:layout_width="match_parent"
    android:visibility="invisible"
    android:layout_height="wrap_content"
    android:orientation="horizontal"
    android:layout_marginTop="30dp"
    >

    <TextView
        android:id="@+id/tvcompletare"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_weight="1"
        android:gravity="center|center_horizontal"
        android:paddingLeft="24dp"
        android:paddingRight="24dp"
        android:text="@string/slide1par5"
        android:textColor="@color/primary"
        android:textSize="15sp" />
</LinearLayout>
</LinearLayout>

Thanks a lot guys!