I recommend you look at resources available on the IRIS website.
https://www.iris-database.org/iris/app/home/index
IRIS is a free public resource of materials used for second language research. If you search for 'collocations', you will see questionnaires/tests used by a number of previous studies in this area.
I need more details on your study to give you an answer. Tell me about the research design and methodology: Was it an intentional/incidental design? Which were the target collocations? Did you pre-test the participants on them? What was the treatment like? What type (strength) of knowledge are you interested in: receptive/productive? Is your focus on durable learning (in which case you need a delayed post-test)?
Dear Per, Verb collocations are to be the target of instruction (intentional design) and the participants are to be tested via mostly fill-in-the-blank questions, i.e their receptive knowledge is to be assessed. Also, I'm interested to see the impact of my instruction on their learning of collocations in both short and long term and they are to be pre-tested on the target collocations. In the attached file you can see part of the researcher-made test.