Keyword Factory
This tool helps you to expand your technical vocabulary using the arXiv dataset.
Note that terms which occur infrequently in arXiv articles will not return good (if any) results.
Read about our method here.
purchase
is associated with:
purchasing,   
e-commerce,   
co-purchase,   
customer,   
shoppers,   
seller,   
purchase-price,   
taobao,   
purchase-order,   
sales,   
shopping,   
post-purchase,   
mnl,   
retailer,   
buyer,   
buy,   
annuity,   
outfits
Using these keywords in combination
with purchase will
help you expand your search horizons.