Simple SOSL scenario:

Create a visual force page:

<apex:page controller="SOSLController">

    <apex:form >

        <apex:inputText value="{!searchStr}"/>

        <apex:commandButton value="Search in Account, Contact, Opportunity" action="{!soslDemo_method}" reRender="acct,error,oppt,cont" status="actStatusId"/>

        <apex:actionStatus id="actStatusId">

            <apex:facet name="start" >

                <img src="/img/loading.gif"/>                    

            </apex:facet>

        </apex:actionStatus>

    </apex:form>

    

    <apex:outputPanel title="" id="error">

        <apex:pageMessages ></apex:pageMessages>

    </apex:outputPanel>

    

    <apex:pageBlock title="Accounts" id="acct">

        <apex:pageblockTable value="{!accList }" var="acc">

            <apex:column value="{!acc.name}"/>

            <apex:column value="{!acc.Type}"/>

        </apex:pageblockTable>

    </apex:pageBlock>

    

    <apex:pageBlock title="Contacts" id="cont">

        <apex:pageblockTable value="{!conList}" var="con">

            <apex:column value="{!con.name}"/>

            <apex:column value="{!con.email}"/>

        </apex:pageblockTable>

    </apex:pageBlock>

    

    <apex:pageBlock title="Opportunities" id="oppt">

        <apex:pageblockTable value="{!optyList}" var="opty">

            <apex:column value="{!opty.name}"/>

            <apex:column value="{!opty.StageName}"/>

        </apex:pageblockTable>

    </apex:pageBlock>

    

</apex:page>

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Public with sharing class SOSLController{

    Public List<Opportunity> optyList {get;set;}

    Public List<contact> conList{get;set;}

    Public List<account> accList{get;set;}

    

    Public String searchStr{get;set;}

    Public SOSLController(){

    }

    

    Public void soslDemo_method(){

        optyList = New List<Opportunity>();

        conList = New List<contact>();

        accList = New List<account>();

        if(searchStr.length() > 1){

            String searchStr1 = '*'+searchStr+'*';

            String searchQuery = 'FIND \'' + searchStr1 + '\' IN ALL FIELDS RETURNING  Account (Id,Name,type),Contact(name,email),Opportunity(name,StageName)';

            List<List <sObject>> searchList = search.query(searchQuery);

            accList = ((List<Account>)searchList[0]);

            conList  = ((List<contact>)searchList[1]);

            optyList = ((List<Opportunity>)searchList[2]);

            if(accList.size() == 0 && conList.size() == 0 && optyList.size() == 0){

                apexPages.addmessage(new apexpages.message(apexpages.severity.Error, 'Sory, no results returned with matching string..'));

                return;

            }

        }

        else{

            apexPages.addmessage(new apexpages.message(apexpages.severity.Error, 'Please enter at least two characters..'));

            return;

        }

    }

}

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