Cannot search with keyword "merge"

Summary

When searching inside a project with the keyword "merge", I obtain a 502 error (which actually looks like a 504) : "Whoops, GitLab is taking too much time to respond.".

• I can reproduce everytime for 1 project whereas it might work for other projects hosted on the same server.
• I can also reproduce with keyword "test" but not for "anything" for example (reserved keywords ?)

Steps to reproduce

0. Try to open https://framagit.org/search?utf8=%E2%9C%93&snippets=&scope=&search=merge&project_id=20776

Example Project

The issue, on the same project, on 3 different servers :

• https://gitlab.com/search?utf8=%E2%9C%93&search=merge&group_id=&project_id=5064860&search_code=true&repository_ref=master
• https://framagit.org/search?utf8=%E2%9C%93&snippets=&scope=&search=merge&project_id=20776
• https://git.phyks.me/search?utf8=%E2%9C%93&search=merge&group_id=&project_id=88&search_code=true&repository_ref=master

What is the current bug behavior?

Error 502.

What is the expected correct behavior?

The search results are returned.

Relevant logs and/or screenshots

I do not own those servers and don't have access to any logs, please ask if I can see with the servers' owners if they can provide anything helpful.