diff --git a/CHANGELOG.md b/CHANGELOG.md
index 0db7ae405..ac5f9052f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,7 @@
 
 ### Features
 - Rely on `intelliLang` plugin to inject `FlexibleSearch` and `Polyglot Query` languages into the Java code [#817](https://github.com/epam/sap-commerce-intellij-idea-plugin/pull/817)
+- Inject `FlexibleSearch` language into the `FlexibleSearchQuery` and its descendants in Java code [#819](https://github.com/epam/sap-commerce-intellij-idea-plugin/pull/819)
 - Added navigation to the `items.xml` Ordering Attribute from the generated classes [#818](https://github.com/epam/sap-commerce-intellij-idea-plugin/pull/818)
 
 ### `Polyglot Query` enhancements
diff --git a/resources/injection/languageInjections.xml b/resources/injection/languageInjections.xml
index e3be47607..b091d695a 100644
--- a/resources/injection/languageInjections.xml
+++ b/resources/injection/languageInjections.xml
@@ -22,12 +22,10 @@
         <display-name>[y] FlexibleSearch</display-name>
         <ignore-pattern>(\\s|.)*GET(\\s|.)*\{(.*)}</ignore-pattern>
         <place><![CDATA[psiModifierListOwner().withText(string().matches("(\\s|.)*=(\\s|.)*SELECT(\\s|.)+FROM(\\s|.)+\\{(\\s|.)*"))]]></place>
-        <place><![CDATA[psiParameter()]]></place>
     </injection>
     <injection language="Polyglot Query" injector-id="java">
         <display-name>[y] Polyglot Query</display-name>
         <ignore-pattern>(\\s|.)*SELECT(\\s|.)*FROM(\\s|.)*\{(\\s|.)*</ignore-pattern>
         <place><![CDATA[psiModifierListOwner().withText(string().matches("(\\s|.)*=(\\s|.)*GET(\\s|.)+\\{(\\s|.)*"))]]></place>
-        <place><![CDATA[psiParameter()]]></place>
     </injection>
 </component>
\ No newline at end of file
diff --git a/src/com/intellij/idea/plugin/hybris/common/HybrisConstants.kt b/src/com/intellij/idea/plugin/hybris/common/HybrisConstants.kt
index c61c54775..2526ac1bf 100644
--- a/src/com/intellij/idea/plugin/hybris/common/HybrisConstants.kt
+++ b/src/com/intellij/idea/plugin/hybris/common/HybrisConstants.kt
@@ -270,7 +270,6 @@ object HybrisConstants {
     const val CLASS_FQN_ITEM_ROOT = "de.hybris.platform.core.model.ItemModel"
     const val CLASS_FQN_ENUM_ROOT = "de.hybris.platform.core.HybrisEnumValue"
     const val CLASS_NAME_ENUM = "HybrisEnumValue"
-    const val CLASS_NAME_FLEXIBLE_SEARCH_SERVICE = "FlexibleSearchService"
     const val CLASS_FQN_INTERCEPTOR_MAPPING = "de.hybris.platform.servicelayer.interceptor.impl.InterceptorMapping"
     const val CLASS_FQN_ANNOTATION_ACCESSOR = "de.hybris.bootstrap.annotations.Accessor"
     const val CLASS_FQN_CONFIG_IMPORT_PROCESSOR = "de.hybris.platform.commerceservices.impex.impl.ConfigPropertyImportProcessor"
diff --git a/src/com/intellij/idea/plugin/hybris/startup/HybrisIntelliLangStartupActivity.kt b/src/com/intellij/idea/plugin/hybris/startup/HybrisIntelliLangStartupActivity.kt
index 0d74c8cd7..c4b492b71 100644
--- a/src/com/intellij/idea/plugin/hybris/startup/HybrisIntelliLangStartupActivity.kt
+++ b/src/com/intellij/idea/plugin/hybris/startup/HybrisIntelliLangStartupActivity.kt
@@ -18,14 +18,20 @@
 package com.intellij.idea.plugin.hybris.startup
 
 import com.intellij.idea.plugin.hybris.common.HybrisConstants
+import com.intellij.idea.plugin.hybris.flexibleSearch.FlexibleSearchLanguage
+import com.intellij.idea.plugin.hybris.polyglotQuery.PolyglotQueryLanguage
 import com.intellij.idea.plugin.hybris.settings.HybrisProjectSettingsComponent
 import com.intellij.openapi.project.DumbService
 import com.intellij.openapi.project.Project
 import com.intellij.openapi.startup.ProjectActivity
+import com.intellij.patterns.PsiJavaPatterns
 import com.intellij.psi.JavaPsiFacade
 import com.intellij.psi.search.GlobalSearchScope
 import com.intellij.psi.search.searches.ClassInheritorsSearch
+import org.intellij.plugins.intelliLang.Configuration
+import org.intellij.plugins.intelliLang.inject.config.InjectionPlace
 import org.intellij.plugins.intelliLang.inject.java.InjectionCache
+import org.intellij.plugins.intelliLang.inject.java.JavaLanguageInjectionSupport
 
 /**
  * TODO: reset Injection Cache on CRUD operation on classes related to FlexibleSearchQuery
@@ -40,6 +46,24 @@ class HybrisIntelliLangStartupActivity : ProjectActivity {
                 add(HybrisConstants.CLASS_NAME_FLEXIBLE_SEARCH_QUERY)
                 addAll(findCustomExtensionsOfTheFlexibleSearch(project))
             }
+
+            val targetLanguages = setOf(FlexibleSearchLanguage.INSTANCE.id, PolyglotQueryLanguage.instance.id)
+
+            // TODO: replace with pattern declared in the XML file once https://youtrack.jetbrains.com/issue/IDEA-339624/ will be resolved.
+            // com.intellij.patterns.compiler.PatternCompiler cannot parse primitive booleans required by the pattern
+            Configuration.getInstance().getInjections(JavaLanguageInjectionSupport.JAVA_SUPPORT_ID)
+                .filter { targetLanguages.contains(it.injectedLanguageId) }
+                .forEach {
+                    val injectionPlaces = it.injectionPlaces.toMutableSet()
+                    val psiParameterInjectionPlace = InjectionPlace(
+                        PsiJavaPatterns.psiParameter().ofMethod(
+                            PsiJavaPatterns.psiMethod().definedInClass(PsiJavaPatterns.psiClass().inheritorOf(false, HybrisConstants.CLASS_FQN_FLEXIBLE_SEARCH_QUERY))
+                        ),
+                        true
+                    )
+                    injectionPlaces.add(psiParameterInjectionPlace)
+                    it.setInjectionPlaces(*injectionPlaces.toTypedArray())
+                }
         }
     }