Hi.
You mentioned word retrieval. To aid with word retrieval, the following games and activities can be useful:
Guessing/describing games - helps children organise their vocabularies by linking words/features to each other which in turn aids word retrieval. Provide a series of clues and children have to guess what you are describing. They also have to hold this information in their auditory memory long enough to be able to assimiliate the clues to come up with the answer. Children can also take turns describing things by features: what it looks like (size, shape, colour), where you find it, what you do with it.
Dice & category game - roll a dice. If the child lands on a five, they have to think of five things that belong in a given category (e.g. things you wear, things you find in the kitchen, transport, basically any category you can think of). You can also encourage them to link sound properties too, e.g. think of two things that are fruits that begin with 'p'.
Sorting games - have a whole heap of household objects / pictures of common objects and encourage your child to put them into categories. Talk about which category things belong in and why (e.g. the spoon and fork go together because they are cutlery.) This helps organise a child's vocabulary (even if it is simple, well-known vocabulary) which aids word retrieval.
Odd one out - have three items (can be things around the house or picture of items). Talk about which one is the odd one out and why (e.g. apple, banana, cake. Cake is the odd one out because it is not a fruit. You can make the odd one out easier if needed, e.g. apple, banana, chair).
New vocabulary - if you introduce the meaning of new words to your child during the holidays, talk about what the words mean, draw/look at pictures of what the words mean, talk about the sounds in the words (first sound, how many syllables/beats, last sound), talk about synonyms, practice using in a sentence.
I'm not sure if you mean auditory or visual memory but here are some auditory memory games and activities:
I went shopping and bought - someone else already mentioned this but is great for auditory memory.
Listening game - have a range of objects in front of your child. Say three or four items all at once (be mindful of not breaking the instruction down as it takes away the memory component of the task) - your child has to listen to the items, remember them, and retrieve them.
Following instructions and relaying messages. You can give your child tasks to do around the house where they have to remember the auditory instruction (e.g. get the towel and the shampoo from the bathroom). You can also encourage your child to relay messages to another person. Chinese whispers can also be played - child has to try and remember the message they heard.
Hope you find these useful. You can adapt them to be approrpiate to your child's level if needed.