Searching using the API

I have a use case where we would want to provide a user suggestions for LOINC codes derived from a non-standard LOINC. I would like to use the API to return all LOINC codes that include words from the “long common name” field of a LOINC, but cannot figure out how to write the query, or if this is even currently possible with the API. Some guidance here would be greatly appreciated.

Forgot to provide an example, and can’t seem to edit my op:

I would want to look up by the word “blood” and have returned a list of LOINCs that have the word blood in them.

I have developed something like that already some time ago. You can find the API description at:
http://xml4pharmaserver.com/WebServices/LOINC_webservices.html#SearchLOINC