From what I know,Vietnam has worse relations with China right now.
What you know is from Western media only. It is totally different to the reality.
General Secretary Nguyen Phu Trong (top leader) visited China in November 2022 and was warmly welcomed by Mr. Xi. German's Chancellor Scholz visited China almost at the same time, but was treated relatively bad.
Earlier this year, US FM Blinken visited Vietnam and invited Mr. Trong to visit the US, but he
de facto declined.
Just few days after Blinken's visit, then comes the unrest in Highland by ethnic minorities, which killed 9 government officials and policemen. During his visit, Blinken met with some representative of those people. We can guess who was behind that unrest, and why. But state media only says that the key personnel who plotted that murder (we do not call it unrest) is living in the US. (Note: no Western media report this killing, which is one of the most severe politic-related crimes in Vietnam since 1975. So much for the "free" media, or I would say, the US-controlled media).
After that, there was an announcement that Mr. Biden would visit Vietnam. His reception in Vietnam was OK, but not special. And this time, no flowers from people on the streets, unlike the 2019 visit of President Trump. From what I can see and read, both sides do not trust each other politically. Only trade has been discussed.
Just 01 day before Mr. Biden's visit, Mr. Trong met with a high-ranking Chinese representative. And just a couple of days after Mr. Biden's visit, Prime Minister Pham Minh Chinh (the second most important) visited Nanning, China for ASEAN - China fair and met with Chinese PM Li Qiang.
And later this year, Chinese top leader Xi Jinping will visit Vietnam.
Now the once very pro-West media port, the popular vnexpress.com, has changed tone in talking about China. There are almost daily articles about science achievement sfrom China, in a positive way.